04. linear equation in one variable
TRANSCRIPT
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kedlshbukerphyslas.ld
>AHES^JW
ILDJ W JUZ ^LOD LD ODJ P WL IJ
Ildjer Jquetlod 6Jquetlod 6 E stetjkjdt o` jqueilty whlah aodtelds
odj or korj udbdowd quedtlty or verlegij (iltjreis) ls
aeiijn ed jquetlod. @or jxekpij -
Jx.5 1x + = ; 57,7
:x < ; 5, x7 + 5 ; : edn
1
x+ : ;
7
x 1 erj jquetlods ld odj verlegij x.
Jx.7 7x + 1y ; 5:, =x 1
y; 1 erj jquetlods ld two
verlegijs x edn y.
Ildjer Jquetlod 6Ed jquetlod ldvoivldm odiy ildjer
poiydokleis ls aeiijn e ildjer jquetlod.
Jx.1 1x 7 ; =,7
1x + < ;
7
5,
1
y+
>
7y ; : erj ildjer
jquetlods ld odj verlegij, gjaeusj thj hlmhjst
powjr o` thj verlegij ld jeah jquetlod ls odj
whjrjes thj jquetlods 1x
7
7x + 5 ; 3, y
7
5 ; 8erj dot ildjer jquetlods, gjaeusj thj hlmhjst powjr
o` thj verlegij ld jeah jquetlod ls dot odj.
Qoiutlod o` e Ildjer Jquetlod 6Qoiutlod 6 E veiuj o` thj verlegij whlah whjd
sugstltutjn `or thj verlegij ld ed jquetlod, kebjs
I.H.Q. ; W.H.Q. ls seln to setls`y thj jquetlod edn ls
aeiijn e soiutlod or e root o` thj jquetlod.
Wuijs `or Qoivldm Ildjer Jquetlods ld Odj
Perlegij 6
Wuij-5 Qekj quedtlty (dukgjr) aed gj ennjn to gothslnjs o` ed jquetlod wlthout ahedmldm thj
jqueilty.
Wuij-7 Qekj quedtlty aed gj sugtreatjn `rok goth slnjs
o` ed jquetlod wlthout ahedmldm thj jqueilty.
Wuij-1 Goth slnjs o` ed jquetlod key gj kuitlpiljn gy
thj sekj dod-zjro dukgjr wlthout ahedmldm thj
jqueilty.
Wuij-> Goth slnjs o` ed jquetlod key gj nlvlnjn gy thj
sekj dod-zjro dukgjr wlthout ahedmldm thj
jqueilty.
Qoivldm Jquetlods hevldm Perlegij ^jrks od OdjQlnj edn Dukgjr(s) od thj Othjr Qlnj 6
JXEKSIJQ
Jx.5 Qoivj thj jquetlod 6:
x+ 55 ;
5:
5edn ahjab thj
rjsuit.
Qoi. ]j hevj,
:
x+ 55 ;
5:
5
:
x+ 55 55 ;
5:
5 55 RQugtreatldm 55
`rok goth slnjs[
:
x;
5:
5 55
:
x;
5:
50:5
:
x;
5:
50>
: :
x; :
5:
50>
x ; 1
50>
^h u s, x ; 1
50>ls thj soiutlod o` thj mlvjd
jquetlod.
Ahjab Qugstltutldm x ;1
50>ld thj mlvjd jquetlod,
wj mjt
I.H.Q. ;:x + 55
;1
50>
:
5+55; 55
5:
50>
;
5:
50:50>;
5:
5edn,
W.H.Q. ;5:
5
I.H.Q. ; W.H.Q. `or x ;1
50>
Hjdaj, x ;1
50>ls thj soiutlod o` thj mlvjd
jquetlod.
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kedlshbukerphyslas.ld
Jx.7 Qoivj 61
5x
7
:; 0
Qoi. ]j hevj,
1
5x
7
:; 0
1
5x
7
:+
7
:; 0 +
7
:REnnldm
7
:od
goth slnjs[
1
5x ; 0 +
7
:
1
5x ;
7
:57
1
5x ;
7
5=
1 1
5x ; 1
7
5=RKuitlpiyldm goth
slnjs gy 1[
x ;7
:5
^ h u s , x ;7
:5ls thj soiutlod o` thj mlvjd
jquetlod.
Ahjab Qugstltutldm x ;7
:5ld thj mlvjd jquetlod, wj mjt
I.H.Q. ;1
5x
7
:;
1
5
7
:5
7
:;
7
5=
7
:
;7
:=5 ;
7
75; 0
edn,W.H.Q. ; 0
I.H.Q. ; W.H.Q. `or x ;7
:5
Hjdaj, x ;7
:5ls thj soiutlod o` thj mlvjd
jquetlod.
Jx.1 Qoivj 67
x
1
x; 8
Qoi. ]j hevj,7
x
1
x; 8
IAK o` njdokldetors 7 edn 1 od I.H.Q. ls 0.
Kuitlpiyldm goth slnjs gy 0, wj mjt
1x 7x ; 0 8 x ; >8
Ahjab Qugstltutldm x ; >8 ld thj mlvjd jquetlod, wj mjt
I.H.Q. ;7
x
1
x;
7
>8
1
>8; 7> 50 ; 8 edn,
W.H.Q. ; 8
I.H.Q. ; W.H.Q. `or x ; >8Hjdaj, x ; >8 ls thj soiutlod o` thj mlvjd
jquetlod.
Jx.> Qoivj 67
x+
1
x
>
x; =
Qoi. ]j hevj,7
x+
1
x
>
x; =
IAK o` njdokldetors 7, 1, > od I.H.Q. ls 57.Kuitlpiyldm goth slnjs gy 57, wj mjt
0x + >x 1x ; = 57
=x ; = 57
=x ; 8>
=
x=;
=
8>RNlvlnldm goth slnjs gy =[
x ; 57
Ahjab Qugstltutldm x ; 57 ld thj mlvjd jquetlod, wj mjt
I.H.Q. ; 7
57
+ 1
57
>
57
; 0 + > 1 ; = edn, W.H.Q.; =
I.H.Q. ; W.H.Q. `or x ; 57.
Hjdaj, x ; 57 ls thj soiutlod o` thj mlvjd
jquetlod.
Jx.: Qoivj 61
5y
>
7y ; 5
Qoi. ]j hevj,1
5y
>
7y ; 5
IAK o` njdokldetors 1 edn > od I.H.Q. ls 57.
Kuitlpiyldm goth slnjs gy 57, wj mjt
57
1
5y 57
>
7y; 57 5
>(y 5) 1(y 7) ; 57
>y > 1y + 0 ; 57 >y 1y > + 0 ;57
y + 7 ; 57
y + 7 7 ; 57 7 RQugtreatldm 7 `rok
goth slnjs[
y ; 53
^hus, y ; 53 ls thj soiutlod o` thj mlvjd jquetlod.
Ahjab Qugstltutldm y ; 53 ld thj mlvjd jquetlod, wj mjt
I.H.Q. ;1
553
>
753 ;
1
8; 1 7 ; 5
edn, W.H.Q. ; 5
I.H.Q. ; W.H.Q. `or y ; 53.
Hjdaj, y ; 53 ls thj soiutlod o` thj mlvjd
jquetlod.
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kedlshbukerphyslas.ld
^redsposltlod Kjthon `or Qoivldm IldjerJquetlods ld Odj Perlegij
^hj tredsposltlod kjthon ldvoivjs thj `oiiowldm
stjps6
Qtjp-L Ogteld thj ildjer jquetlod.Qtjp-LL Lnjdtl`y thj verlegij (udbdowd quedtlty)
edn aodstedts(dukjreis).
Qtjp-LLL Qlkpil`y thj I.H.Q. edn W.H.Q. to thjlr
slkpijst `orks gy rjkovldm greabjts.
Qtjp-LP ^redsposj eii tjrks aodteldldm verlegij
od I.H.Q. edn aodstedt tjrks od W.H.Q.
Dotj thet thj slmd o` thj tjrks wlii
ahedmj ld shl`tldm thjk `rok I.H.Q. to
W.H.Q. edn vlaj-vjrse.
Qtjp-P Qlkpil`y I.H.Q. edn W.H.Q. ld thj slkpijst
`ork so thet jeah slnj aodtelds fust odj
tjrk.
Qtjp-PL Qoivj thj jquetlod ogteldjn ld stjp P
gy nlvlnldm goth slnjs gy thj aoj``laljdt
o` thj verlegij od I.H.Q.
JXEKSIJQ
Jx.5 Qoivj 67
x
:
5;
1
x+
>
5
Qoi. ]j hevj,7
x
:
5;
1
x+
>
5
^hj njdokldetors od two slnjs erj 7, :, 1 edn >.
^hjlr IAK ls 03. Kuitlpiyldm goth slnjs o` thj
mlvjd jquetlod gy 03, wj mjt
03
:
5
7
x; 03
>
5
1
x
03 7
x 03
:
5; 03
1
x+ 03
>
5
13x 57 ; 73x + 5: 13x 73x ; 5: + 57 ROd tredsposldm 73x to
IHQ edn 57 to WHQ[
53x ; 7=
x ;53
7=
Hjdaj, x ;537= ls thj soiutlod o` thj mlvjd
jquetlod.
Ahjab Qugstltutldm x ;53
7=ld thj mlvjd jquetlod, wj mjt
I.H.Q. ;:
5
53
7=
:
5
7
5
53
7=
:
5
7
x
;73
71
73
>7=
73
>57=
edn,
W.H.Q. ;>
5
1
5
53
7=
>
5
1
x
;73
71
73
:58
73
:57
5
53
.
Kuitlpiyldm goth slnjs o` thj mlvjd jquetlod 7>,
wj mjt
7>
1
x8=x ; 7>
8
x:
0
5=
7>x + 7> = 7> 1
x8; 7>
0
5= 7>
8
x:
7>x + 508 0>x ; 08 5:x 508 >3x ; 08 5:x >3x + 5:x ; 08 508 R^redsposldm 5:x
to IHQ edn 508 to WHQ[
7:x ; 533 7:x ; 533
x ;7:
533RNlvlnldm goth slnjs gy 7:[
x ; >
^hus, x ; > ls thj soiutlod o` thj mlvjd jquetlod.
Ahjab Qugstltutldm x ; > ld thj mlvjd jquetlod, wj mjt
I.H.Q. ; x + = 1
x8; > + =
1
>8
; 55 1
17;
1
1711 ;
1
5
edn, W.H.Q. ;0
5=
8
x:;
0
5=
8
>:;
0
5=
7
:
;0
5:5= ;
0
7;
1
5
^hus, `or x ; >, wj hevj I.H.Q. ; W.H.Q.
Jx.1 Qoivj 6>
7t1
1
1t7 ;
1
7 t
Qoi. ]j hevj,>
7t1
1
1t7 ;
1
7 t
^hj njdokldetors od two slnjs erj >, 1 edn 1.
^hjlr IAK ls 57.
Kuitlpiyldm goth slnjs o` thj mlvjd jquetlod gy
57, wj mjt
57
>
7t1 57
1
1t7; 57
t
1
7
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kedlshbukerphyslas.ld
1(1t 7) >(7t + 1) ; 57
t
1
7
771 1
177 ; >
70
1
1>
1
=
>
> ; 5
1
=;
1
=1 ;
1
>
edn,
W.H.Q. ;1
7 t ;
1
7 7 ;
>
07 ;
1
>
^hus, `or t ; 7, wj hevj I.H.Q. ; W.H.Q.
Jx.> Qoivj 60
7x
>
5
1
x55;
57
>x1
Qoi. ]j hevj,0
7x
>5
1x55 ;
57>x1
^hj njdokldetors od two slnjs o` thj mlvjd
jquetlod erj 0, 1, > edn 57. ^hjlr IAK ls 7>.
Kuitlpiyldm goth slnjs o` thj mlvjd jquetlod gy
7>, wj mjt
7>
0
7x 7>
>
5
1
x55; 7>
57
>x1
>(x + 7) 7>
1
x55+ 7>
>
5; 7(1x >)
>(x + 7) 8(55 x) + 0 ; 7(1x >) >x + 8 88 + 8x + 0 ; 0x 8
57x => ; 0x 8 57x 0x ; => 8 R^redsposldm 0x to IHQ
edn => to WHQ[
0x ; 00
x ;0
00RNlvlnldm goth slnjs gy 0[
x ; 55Ahjab Qugstltutldm x ; 55 od goth slnjs o` thj mlvjd
jquetlod, wj mjt
I.H.Q. ;0
7x
>
5
1
x55
;0
755
>
5
1
5555;
0
51
>
53
;0
51+
>
5;
57
170 ;
57
7x1 ; 57
>551 ; 57
>11 ; 57
7
5
0
x7x 1
Qoi. ]j hevj,
x 1
8x7 ;
>
5
0
x7x 1
x 1
8x7 ;
>
x
7>
x7 1
^hj njdokldetors od thj two slnjs o` thls
jquetlod erj 1, > edn 7>. ^hjlr IAK ls 7>.
Kuitlpiyldm goth slnjs o` thls jquetlod gy 7>,wj mjt
7>x 7>
1
8x7;7>
>
x 7>
7>
x7 1 7>
7>x 8(7x + 8) ; 0x (7 x) =7 7>x 50x 0> ; 0x 7 + x =7 8x 0> ; =x => 8x =x ; 0> => R^redsposldm =x to IHQ
edn 0> to WHQ[
x ; 53^hus, x ; 53 ls thj soiutlod o` thj mlvjd
jquetlod.
Ahjab Suttldm x ; 1
8x7 ; 53 1
8537
; 53 1
873 ; 53
1
57; 53 + > ; 0
edn,
W.H.Q. ;>
5
0
x7x 1 ;
>
5
0
53753 1
;>
5(53 7) 1 ; 1 1 ; 0
^hus, I.H.Q. ; W.H.Q. `or x ; 53.
Jx.0 Qoivj 6 3.50(:x 7) ; 3.>x + =
Qoi. ]j hevj,3.50(:x 7) ; 3.>x + =
3.8x 3.17 ; 3.>x + = RJxpednldm thjgreabjt od IHQ[
3.8x 3.>x ; 3.17 + = R^redsposldm 3.>x toIHQ edn 3.17 to WHQ[
3.>x ; =.17
>.3
x>.3;
>.3
17.=
x ;>3
=17 x ;
53
581; 58.1
Hjdaj, x ; 58.1 ls thj soiutlod o` thj mlvjd
jquetlod.
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kedlshbukerphyslas.ld
Jx.= Qoivj 6x:
7
x1
:;
5:
5
Qoi. ]j hevj,x:
7
x1
:;
5:
5
Kuitlpiyldm goth slnjs gy 5:x, thj IAK o` :x
edn 1x, wj mjt
5:x x:
75:x
x1
:; 5:x
5:
5
0 7: ; x 5< ; x x ; 5 ; : 0x +
1
5>x=
Qoi. Kuitlpiyldm goth slnjs gy 5: l.j. thj IAK o` :
edn 1, wj mjt
1(5= 1x) :(>x + 7)
; 5:(: 0x) + :(=x + 5>)
:5 5 70 x ; 53>
70
x70;
70
53>
x ; >^hus, x ; > ls thj soiutlod o` thj mlvjd jquetlod.
Jx.< Qoivj 61
7x
:
5x;
>
1x 5
Qoi. Kuitlpiyldm goth slnjs gy 03 l.j. thj IAK o` 1,
:, edn >, wj mjt
73(x + 7) 57(x + 5) ; 5:(x 1) 5 03
73x + >3 57x + 57 ; 5:x >: 03 8x + 78 ; 5:x 53: 8x 5:x ; 53: 78 =x ; 511
=
x=
;
=
511
RNlvlnldm goth slnjs gy =[
x ;=
511; 5x7 + Hjdaj, x ; > ls thj soiutlod o` thj mlvjd jquetlod.
Jx.7 Qoivj 6=x7
:x1
; >
Qoi. ]j hevj,=x7
:x1
; >
=x7
:x1
;
>
5
5 (1x + :) ; > (7x + =)RGy aross-kuitlpilaetlod[
1x + : ; 8x + 78 1x 8x ; 78 : RZsldm tredsposltlod[ :x ; 71
:
x:
;
:
71
x ; :
71
Hjdaj, x ; :
71ls thj soiutlod o` thj mlvjd
jquetlod.
Jx.1 Qoivj 6x=5
)57x(:)x7(5=
; 8
Qoi. ]j hevj,x=5
)57x(:)x7(5=
; 8
x=5
03x:x5=1>
;
5
8
x=5
70x77
;
5
8
5 ( 77x 70) ; 8 (5 =x)RGy aross-kuitlpilaetlod[
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kedlshbukerphyslas.ld
77x 70 ; 8 :0x 77x + :0x ; 8 + 70 1>x ; 1>
1>
x1>;
1>
1>
Hjdaj, x ; 5 ls thj soiutlod o` thj mlvjd jquetlod.
Jx.> Qoivj 6ge
gx
;
ge
gx
Qoi. ]j hevj,ge
gx
;
ge
gx
(x + g) (e + g) ; (x g) (e g)RGy aross-kuitlpilaetlod[
x (e + g) + g(e + g) ; x(e g) g(e g) ex + gx + ge + g7 ; ex gx ge g 7
ex + gx ex + gx ; gx + g7 ge g7
7gx ; 7ge
g7
gx7;
g7
eg7
x ; eHjdaj, x ; e ls thj soiutlod o` thj mlvjd jquetlod.
Jx.: Qoivj 6)x=)(x7(
)x:)(x>(
; 5
Qoi. ]j hevj,)x=)(x7(
)x:)(x>(
; 5
7
7
xx=x75>
xx:x>73
; 5
7
7
xx:5>
xx73
; 5
73 + x x7 ; 5> + :x x7
RGy aross-kuitlpilaetlod[
x x7 ; :x + x7 ; 5> 73 >x ; 0
>
x>
;
>
0
x ;7
1
Hjdaj, x ; 7
1
ls thj soiutlod o` thj mlvjd jquetlod.
Jx.0 Qoivj 65x
5
+
7x
5
;
53x
7
Qoi. ]j hevj,5x
5
+
7x
5
;
53x
7
Kuitlpiyldm goth slnjs gy (x + 5)(x + 7)(x + 53)
l.j., thj IAK o` x + 5, x + 7 edn x + 53, wj mjt
5x
)53x)(7x)(5x(
+
7x
)53x)(7x)(5x(
;
53x
)53x)(7x)(5x(7
(x + 7)(x + 53) ; (x + 5)(x + 53); 7(x + 5)(x + 7)
x7 + 7x + 53x + 73 + x7 + 53x + x + 53; 7(x7 + x + 7x + 7)
7x7 + 71x + 13 ; 7(x7 + 1x + 7)
7x7
+ 71x + 13 ; 7x7
+ 0x + > 7x7 + 71x 7x7 + 0x ; > 13 5=x ; 70
x ; 5=
70
Hjdaj, x ; 5=
70ls thj soiutlod o` thj mlvjd
jquetlod.
Jx.= Qoivj 6:x7
>x51x0 7
;
1x>
7x:x57 7
Qoi. ]j hevj,:x7
>x51x0 7
;
1x>
7x:x57 7
(0x7 + 51x >)(>x + 1); (57x7 + :x 7)(7x + :)
RGy aross-kuitlpilaetlod[
(0x7 + 51x >) >x + (0x7 + 51x >) 1; (57x7 + :x 7) 7x + (57x7 + :x 7) :
7>x1 + :7x7 50x + 58x7 + 1x1 + 53x7 >x + 03x7 + 7:x 53
7>x1 + =3x7 + 71x 57; 7>x1 + =3x7 + 57x 53
7>x1 + =3x7 + 71x 7>x1 =3x7 75x; 53 + 57
7x ; 7 x ; 5Hjdaj, x ; 5 ls thj soiutlod o` thj mlvjd jquetlod.
Jx.8 Qoivj 658
5=x>
17x5=
7x51
+
1
x;
57
x=
10
50x
Qoi. ]j hevj,
58
5=x>
17x5=
7x51
+
1
x;
57
x=
10
50x
58
5=x>
57
x=+
10
50x+
1
x;
17x5=
7x51
Kuitlpiyldm goth slnjs gy 10 l.j., thj IAK o` 58,
57, 10 edn 1, wj mjt
10 58
5=x> 10
57
x=+ 10
10
50x+ 10
1
x
; 10
17x5=
7x51
7(>x + 5=) 1 =x + x + 50 + 57x
; 10
17x5=
7x51
8 x + 1 > 7 5 x + x + 5 0 + 5 7 x ; 1 0
17x5=
7x51
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kedlshbukerphyslas.ld
:3 ; 10
17x5=
7x51RGy aross-
kuitlpilaetlod[
:3 (5=x 17) ; 10(51x 7) 8:3x 5033 ; >08x =7
8:3x >08x ; 5033 =7 187x 5:78
x ;187
5:78; >
Hjdaj, x ; > ls thj soiutlod o` thj mlvjd jquetlod.
Eppilaetlods o` Ildjer Jquetlods toSreatlaei Srogijks
^hj `oiiowldm stjps shouin gj `oiiowjn to soivj
e worn progijk6
Qtjp-L Wjen thj progijk aerj`uiiy edn dotj
whet ls mlvjd edn whet ls rjqulrjn.Qtjp-LL Njdotj thj udbdowd quedtlty gy sokj
ijttjrs, sey x, y, z, jta.
Qtjp-LLL ^redsietj thj stetjkjdts o` thj progijk
ldto kethjketlaei stetjkjdts.
Qtjp-LP Zsldm thj aodnltlod(s) mlvjd ld thj
progijk, `ork thj jquetlod.
Qtjp-P Qoivj thj jquetlod `or thj udbdowd.
Qtjp-PL Ahjab whjthjr thj soiutlod setls`ljs thj
jquetlod.
JXEKSIJQJx.5 E dukgjr ls suah thet lt ls es kuah mrjetjr thed
8> es lt ls ijss thed 538. @ldn lt.
Qoi. Ijt thj dukgjr gj x. ^hjd, thj dukgjr ls mrjetjr
thed 8> gy x 8> edn lt ls ijs thed 538 gy
538 x. RMlvjd[
x 8> ; 538 x x + x ; 538 + 8> 7x ; 5
x
1
x
Lt ls mlvjd thet thj dukgjr x ls :0 mrjetjr thed
thj evjremj o` thj thlrn, quertjr edn odj-twji`tho` x.
x ;1
5
57
x
>
x
1
x+ :0
x ; x). Lt
ls mlvjd thetth
=
>
o` odj pert ;
th
:
7
o` thj othjr pert
=> x ;
:7 (1> x)
73x ; 5>(1> x) RKuitlpiyldm goth slnjs gy1:, thj IAK o` = edn :[
73x ; 5> 1> 5>x 73x + 5>x 5> 1> 1>x ; 5> 1>
1>
x1>;
1>
1>5>RNlvlnldm goth slnjs gy 1>[
x ; 5>Hjdaj, thj two perts erj 5> edn 1> 5> ; 73
Jx.: ^hj dukjretor o` e `reatlod ls > ijss thet thj
njdokldetor. L` 5 ls ennjn to goth lts dukjretoredn njdokldetor, lt gjaokjs 5/7. @ldn thj
`reatlod.
Qoi. Ijt thj njdokldetor o` thj `reatlod gj x. ^hjd,
Dukjretor o` thj `reatlod ; x >
@reatlod ;x
>x ...(l)
L ` 5 l s e nn jn t o g o t h l ts d uk jr et or e dn
njdokldetor, thj `reatlod gjaokjs7
5.
5x
5>x
;
7
5
5x
1x
;
7
5
7(x 1) ; x + 5 RZsldm aross-kuitlpilaetlod[ 7x 0 ; x + 5 7x x ; 0 + 5 x ; =Suttldm x ; = ld (l), wj mjt
@reatlod ;=
>= ;
=
1.
Hjdaj, thj mlvjd `reatlod ls=
1.
Jx.0 Qeuregh hes Ws 1> pelsj edn twjdty-`lvj pelsjaolds. L` thj dukgjr o` 7:-pelsj aolds gj twlaj
thj dukgjr o` :3-pelsj aolds, how kehy aolds o`
jeah bldn nojs hj hevj ?
Qoi. Ijt thj dukgjr o` :3-pelsj aolds gj x. ^hjd,
Dukgjr o` 7:-pelsj aolds ; 7x
Peiuj o` x `l`ty-pelsj aolds ; :3 x pelsj
; Ws533
x:3; Ws
7
x
Peiuj o` 7x twjdty-`lvj pelsj aolds ; 7: 7x pelsj
; Ws533
x:3; Ws
7
x
^otei veiuj o` eii aolds ; Ws
7
x
7
x; Ws x
Gut, thj totei veiuj o` thj kodjy ls Ws 1>
x ; 1>
^hus, dukgjr o` :3-pelsj aolds ; 1>Dukgjr o` twjdty-`lvj pelsj aolds
; 7x ; 7 1> ; 08
Jx.= Ervldn hes Slmmy gedb. Lt ls `uii o` odj-rupjj
edn `l`ty-pelsj aolds. Lt aodtelds 1 tlkjs es kedy
`l ty pelsj aolds es odj rupjj aolds. ^hj totei
ekoudt o` thj kodjy ld thj gedb ls Ws 1:. How
kedy aolds o` jeah bldn erj thjrj ld thj gedb ?
Qoi. Ijt thjrj gj x odj rupjj aolds ld thj gedb. ^hjd,
Dukgjr o` :3-pelsj aolds ; 1x
Peiuj o` x odj rupjj aolds ; Ws x
Peiuj o` 1x `l`ty-pelsj aolds ; :3 1x pelsj
; 5:3 x ; pelsj ; Ws533
5:3x ; Ws
7
x1
^otei veiuj o` eii thj aolds ; Ws
7
x1x
Gut, thj totei ekoudt o` thj kodjy ld thj ged ls
mlvjd es Ws 1:.
x +7
x1; 1:
7x + 1x ; =3 RKuitlpiyldm goth slnjs gy 7[
:x ; =3 :x: ;
:=3 x ; 5>
Dukgjr o` odj rupjj aolds ; 5>, Dukgjr o`:3 pelsj aolds ; 1x ; 1 5> ; >7.
Jx.8 Bedwer ls thrjj yjers oinjr thed Edlke. Qlx yjers
emo, Bedwers emj wes `our tlkjs Edlkes emj.
@ldn thj emjs o` Bdewer edn Edlke.
Qoi. Ijt Edlkes emj gj x yjers. ^hjd, Bedwers emj
ls (x + 1) yjers.
Qlx yjers emo, Edlkes emj wes (x 0) yjers
Lt ls mlvjd thet slx yjers emo Bedwers emj wes
`our tlkjs Edlkes emj. x 1 ; >(x 0)
x 1 ; >x 7>
x >x ; 7> + 1
1x ; 75
1
x1
;
1
75
x ; =
Hjdaj, Edlkes emj ; = yjers
Bedwers emj ; (x + 1) yjrs
; (= + 1) yjers ; 53 yjers.
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Jx.< Hekln hes thrjj goxjs o` nl``jrjd rults. Gox E
wjlmhs 77
5bm korj thed Gox G edn Gox A wjlmhs
53>
5bm korj thed Gox G. ^hj totei wjlmht o` thj
goxjs ls >8>
1Hox kedy bm nojs Gox E wjlmh ?
Qoi. Qupposj thj gox G wjlmhts x bm.
Qlda gox E wjlmhs 77
5bm korj thed gox G edn
A wjlmhs 53>
5bm korj thed gox G.
]jlmht o` gox E ;
7
57x bm
;
7
:x bm ... (l)
]jlmht o` gox A ;
>
553x bm
;
>
>5x bm
^otei wjlmht o` eii thj goxjs
;
>
>5xx
7
:x bm
Gut, thj totei wjlmht o` thj goxjs ls mlvjd es
>8>
1bm ;
>
5
>5; >
5x + 53 + >x + >x + >5 ; 5[
57x + :5 ; 5
57
x57;
57
5>>
x ; 57Suttldm x ; 57 ld (l), wj mjt
]jlmht o` gox E ;
7
:57 bm ; 5>
7
5bm.
Jx.53 E ked soin ed ertlaei `or Ws >:3
Hjdaj, aost prlaj o` thj ertlaij ; Ws >:3.
Jx.55 :3 bm o` ed eiioy o` ijen edn tld aodtelds :3%
ijen. How kuah ijen kust gj kjitjn ldto lt to
kebj ed eiioy aodteldldm =:% ijen ?
Qoi. Ijed aodtjdts ld 533 bm eiioy ; 03 bm Ijen aodtjdts ld :3 bm eiioy
;
:3
533
03bm ; 13 bm
Ijt x bm o` ijen gj kjitjn ldto thj eiioy to kebj
lt ed eiioy aodteldldm =:% ijen. ^hjd,
]jlmht o` thj djw eiioy ; (:3 + x) bm
]jlmht o` ijen ld thj djw eiioy ; (13 + x) bm
Dow,
Ijen aodtjdts ld (:3 + x)bm eiioy ; (13 + x)bm
Ijen aodtjdts ld odj bm eiioy ;
x:3x13 bm
Ijen aodtjdts ld 533 bm eiioy
;
x:3
x13 533 bm
Sjrajdtemj o` ijen ld djw eiioy
;
533
x:3
x13%
Gut, thj pjrajdtemj o` ijen ld thj djw eiioy ls
mlvjd es =:%.
x:3
x13
533 ; =:
(13 + x) 533 ; =: (:3 + x)
RZsldm aross-kuitlpilaetlod[
1333 + 533x ; 1=:3 + =:x
533 x =:x ; 1=:3 1333
7:x ; =:3
7:
x7:;
7:
=:3
x ; 13
Hjdaj, rjqulrjn ijen to gj ennjn ; 13 bm.
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Jx.57 ^hj suk o` two dukgjrs ls 7>55 @lrst dukgjr ; 5>55, Qjaodn dukgjr
; 7>55 ; 53=55 ;
5333
:. ^hjrj`orj, thj othjr dukgjr
wlii gj >: x.
Lt ls mlvjd thet thj retlo o` thj dukgjrs ls = 6 8.
x>:
x
;
8
=
8 x ; = (>: x) RGy aross-uitlpilaetlod[ 8x ; 15: =x 8x + =x ; 15: 5:x ; 15:
x ;5:
15:; 75
^hus, odj dukgjr ls 75 edn, Othjr dukgjr
; >: x ; >: 75 ; 7>
Ahjab Aijeriy, suk o` thj dukgjrs ; 75 + 7> ; >:, whlah
ls sekj es mlvjd ld thj progijk.
Wetlo o` thj dukgjrs ; 7>
75
; 8
=
, whlah ls sekj esmlvjd ld thj progijk.
^hus, our soiutlod ls aorrjat.
Jx.5> Nlvlnj Ws 5183 ekodm Ehkjn, Fohd edn Geglte
so thet thj ekoudt Ehkjn rjajlvjs ls : tlkjs e
skuah es Gegltes sherj edn ls 1 tlkjs es kuah
es Fohds sherj.
Qoi. Ijt Gegltes sherj gj Ws x. ^hjd,
Ehkjns sherj ; Ws :x
Fohds sherj ; ^otei ekoudt (Gegltessherj + Ehkjns sherj)
; WsR5183 (x + :x)[ ; Ws (5183 0x)Lt ls mlvjd thet Ehkjns sherj ls thrjj tlkjs
Fohds sherj.
:x ; 1(5183 0x) :x ; >5>3 58x :x + 58x ; >5>3 71x ; >5>3
x ;71
>5>3; 583
Gegltes sherj ; Ws 583, Ehkjns sherj; Ws(: 583) ; Ws ak. L` ijdmth edn grjenth erj jeah ldarjesjn gy
1 ak, thj erje o` thj djw rjatedmij wlii gj 85 ak7
korj thed thet o` thj mlvjd rjatedmij. @ldn thj
ijdmth edn grjenth o` thj mlvjd rjatedmij.
Qoi. Ijt thj grjenth o` thj mlvjd rjatedmij gj x ak.
^hjd, Ijdmth ; (x + >) ak
Erje ; Ijdmth Grjenth ; (x + >)x ; x7 + >x.]hjd ijdmth edn grjenth erj jeah ldarjesjn gy
1 ak.
Djw ijdmth ; (x + > + 1) ak ; (x + =) ak,
Djw grjenth ; (x + 1) ak
Erje o` djw rjatedmij ; Ijdmth Grjenth; (x + =) (x + 1)
; x(x + 1) + =(x + 1)
; x7 + 1x + =x + 75 ; x7 + 53x + 75
Lt ls mlvjd thet thj erj o` djw rjatedmij ls 85 ak7
korj thed thj mlvjd rjatedmij.
x7 + 53x + 75 ; x7 + >x + 85 x7 + 53x x7 >x ; 85 75 0x ; 03
x ;0
03; 53
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^hus,
Ijdmth o` thj mlvjd rjatedmij
; (x + >)ak ; (53 + >) ak ; 5> ak
Grjenth o` thj mlvjd rjatedmij ; 53 ak
Ahjab Erje o` thj mlvjd rjatedmij ; (x7 + >x)ak7
; (537
+ > 53)ak7
; 5>3 ak7
Erje o` thj djw rjatedmij ; (x7 + 53x + 75)ak7
; (537 + 53 53 + 75)ak7 ; 775 ak7
Aijeriy, erje o` thj djw rjatedmij ls 85 ak7 korj
thed thet o` thj mlvjd rjatedmij, whlah ls thj
sekj es mlvjd ld thj progijk. Hjdaj, our edswjr
ls aorrjat.
Jx.50 Ed eitltutnj o` e trledmij ls lvj-thlrns thj ijdmth
o` lts aorrjspodnldm gesj. L` thj eitltunj wjrj
ldarjesjn gy > ak edn thj gesj gj njarjesjn gy
7 ak, thj erje o` thj trledmij wouin rjkeld thj
sekj. @ldn thj gesj edn thj eitltunj o` thj
trledmij.
Qoi. Ijt thj ijdmth o` thj gesj o` thj trledmij gj x ak.
^hjd,
Eitltunj ;
x
1
:ak ;
1
x:ak
Erje ;7
5(Gesj Eitltunj) ak7
;
1
x:x
7
5ak7 ;
0
x: 7
ak7
]hjd thj eitltunj ls ldarjesjn gy > ak edn thj
gesj ls njarjesjn gy 7 ak, wj hevj
Djw gesj ; (x 7) ak, Djw eitltunj ;
>
1
x:ak
Erje o` thj djw trledmij
;7
5(Gesj Eitltunj)
;7
5
)7x(>
1
x:ak7
;7
5
>
1
x:)7x( ak7
;75
)7x(>)7x(
1x: ak7
;7
5
8x>1
x53
1
x: 7
ak7
;7
5
>x7
1
x:
0
x: 7
ak7
Lt ls mlvjd thet thj erje o` thj mlvjd trledmij ls
sekj es thj erje o` thj djw trledmij.
0
x: 7
;0
x: 7
1
x:+ 7x >
0
x: 7
0
x: 7
+1x: 7x ; >
1
x: 7x ; > RKuitlpiyldm goth slnjs gy 1[
x ; 57 x ; 57akHjdaj, gesj o` thj trledmij ; 57 ak.
Eitltunj o` thj trledmij ;
57
1
:ak ; 73 ak
Ahjab ]j hevj,
Erje o` thj mlvjd trledmij ;
757
0
:ak ; 573ak7
Erje o` thj mlvjd trledmij
;
>57757
1
5:57
0
: 7ak ; 573ak7
^hjrj`orj, erje o` thj mlvjd trledmij ls thj sekj
es thet o` thj djw trledmij, whlah ls thj sekj es
mlvjd ld thj progijk. ^hus, our edswjr ls aorrjat.
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U.5 E dukgjr ls es kuah mrjetjr thed 10 es ls ijss
thed 80. @ldn thj dukgjr.
U.7 @ldn e dukgjr suah thet whjd 5: ls sugtreatjn
`rok = tlkjs thj dukgjr, thj rjsuit ls 53 korj
thed twlxj thj dukgjr.
U.1 ^hj suk o` e retlodei dukgjr edn lts rjalproaei
ls0
51. @ldn thj dukgjr..
U.> ^hj suk o` two dukgjrs ls 58>. L` odj-thlrn o`
thj odj jxajjns odj-sjvjdth o` thj othjr gy 8,
`ldn thj skeiijr dukgjr.
U.: ^hj nl `jrjdaj o` two dukgjrs ls 55 edn odj-`l`th o` thjlr suk ls 7 edn thjlr pronuat
ls >1=, thjd `ldn thj egsoiutj nl``jrjdaj gjtwjjd
thj dukgjrs.
U.= ^hj suk o` two dukgjrs ls 5: edn thj suk o`
thjlr squerjs ls 551. @ldn thj dukgjrs.
U.8 ^hj evjremj o` `our aodsjautlvj jvjd dukgjrs
ls 7=. @ldn thj iermjst o` thjsj dukgjrs.
U.< ^hj suk o` thj squerjs o` thrjj aodsjautlvj ondukgjrs ls 7:15. @ldn thj dukgjrs.
U.53 O` two dukgjrs, > tlkjs thj skeiijr odj ls ijss
thed 1 tlkjs thj iermjr odj gy :. L` thj suk o`
thj dukgjrs ls iermjr thed : tlkjs thjlr nl``jrjdaj
gy 0, `ldn thj two dukgjrs.
U.55 ^hj retlo gjtwjjd e two-nlmlt dukgjr edn thj
suk o` thj nlmlts o` thet dukgjr ls > 6 5. L` thj
nlmlt ld thj udlts pieaj ls 1 korj thed thj nlmlt
ld thj tjds pieaj, whet ls thj dukgjr ?
U.57 E dukgjr aodslsts o` two nlmlts. ^hj suk o` thjnlmlts ls :3 ls nlvlnjn ldto two perts suah thet thj suk o`
thjlr rjalproaeis ls75
5. @ldn thj two perts.
U.5: L` thrjj dyukgjrs erj ennjn ld pelrs, thj suks
jquei 53, 5< edn 75. @ldn thj dukgjrs.
U.50 Wefjjvs emj e`tjr 5: yjers wlii gj : tlkjs hls emj
: yjers geab. ]het ls tj prjsjdt emj o` Wefjjv?
U.5= ^hj emjs o` two pjrsods nl``jrj gy 50 yjers. L`
0 yjers emo, thj jinjr odj gj 1 tlkjs es oin es
thj youdmjr odj, `ldn thjlr prjsjdt emejs.
U.58 ^hj pronuat o` thj emjs o` Edbjt edn Dlblte ls
7>3 . L` twlaj thj emj or Dlblte ls korj thed
Edblts emj gy > yjers, whet ls Dlbltes emj?
U.5< ^hj prjsjdt emj o` e `ethjr ls 1 yjers korj thedthrjj tlkjs thj emj o` hls sod. ^hrjj yjers hjdaj,
`ethjrs emj wlii gj 53 yjers korj thed twlaj thj
emj o` thj sod. @ldn thj prjsjdt emj o` thj `ethjr.
U.73 Wohlt wes > tlkjs es oin es hls sod 8 yjers emo.
E`tjr 8 yjers, Wohlt wlii gj wtlaj es oin es hls
sod. ]het erj thjlr prjsjdt emjs ?
U.75 Odj yjer emo, thj retlo o` Meurevs edn Qeahlds
emj wes 0 6 = rjspjatlvjiy. @our yjers hjdaj, thls
retlo wouin gjaokj = 6 8. How oin ls Qeahld ?
U.77 Egheys emj e`tjr slx yjers wlii gj thrjj-sjvjdth
o` hls `ethjrs emj et prjsjdt ?
EDQ]JWQ
5. 05 7. : 1. 7 /1 or 1/7 >.=7 :. 78 & 5= 0. >
=. = & 8 8.13 . 13 & 73 5:. 0, >, 5: 50. 53 yjers 5=. 5> & 13 yjers 58. 57 yjers
53 yjers 75. 10 yjers 77. :3 yjers
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U.5 ^h j n l ``j rjd j g j tw jj d e d uk g jr e dn l t s
thrjj-`l`th ls :3. ]het ls thj dukgjr ?
(E) =: (G) 533(A) 57: (N) Dodj o` thjsj
U.7 L` e dukgjr ls njarjesjn gy > edn nlvlnjn gy 0,
thj rjsuit ls 8. ]het wouin gj thj rjsuit l` 7 ls
sugtreatjn `rok thj dukgjr edn thjd lt ls nlvlnjn
gy :?
(E) : (N) :>
U.> E dukgjr ls nougijn edn < ls ennjn. L` thj
rjsuitedt ls trjgijn, lt gjaokjs =:. ]het ls thet
dukgjr ?
(E) 1.: (G) 0
(A) 8 (N) Dodj o` thjsj
U.: ^hrjj-`ourth o` e dukgjr ls 03 korj thed lts odj-
thlrn. ^hj dukgjr ls 6
(E) 8> (G) 538
(A) 5>> (N) Dodj o` thjsj
U.0 ]hjd 7> ls sugtreatjn `roke dukgjr, lt rjnuajs
to lts `our-sjvjdth. ]het ls thj suk o` thj nlmlts
o` thet dukgjr?
(E) 5 (G) , ls rjnuajn gy 75,
thj dukgjr ls 6
(E) 58 (G) 73 (A) 78 (N) 18
U.< E dukgjr whosj `l th pert ldarjesjn gy > ls
jquei to lts `ourth pert nlkldlshjn gy 53, ls
(E) 7>3 (G) 703
(A) 7=3 (N) 783
U.53 ^hj nl` jrjdaj o` two dukgjrs ls 73% o` thj
iermjr dukgjr. L` thj skeiijr dukgjr ls 57, thj
iermjr odj ls 6
(E) 5: (G) 50
(A) 58 (N) 73
U.55 L` odj-sjvjdth o` e dukgjr jxajjns lts jijvjdth
pery gy 533, thjd thj dukgjr ls 6
(E) ==3 (G) 5533(A) 587: (N) 5 `rok thj pronuat, thj
dukgjr ls6
(E) 7 (G) 1 (A) > (N) 0
U.5> L` :3 ls sugtreatjn `rok two-thlrn o` e dukgjr,
thj rjsuit ls jquei to suk o` >3 edn odj-`ourth
o` thet dukgjr. ]het ls thj dukgjr ?
(E) 5=> (G) 750 (A) 7>0 (N) 110
U.5: L` thj suk o` e dukgjr edn lts squerj ls 587,
whet ls thj dukgjr ?
(E) 5: (G) 70
(A) 78 (N) Dodj o` thjsj
U.50 ^wjdty tlkjs e posltlvj ldtjmjr ls ijss thed ltssquerj gy
(A) Aeddot gj njtjrkldjn
(N) Dodj o` thjsj
U.5= ^hrlaj thj squerj o` e deturei dukgjr njarjesjn
gy > tlkjs thj dukgjr ls jquei to :3 korj thed
thj dukgjr. ^hj dukgjr ls 6
(E) > (G) : (A) 0 (N) 53
U.58 ^hj suk o` e dukgjr edn lts rjalproaei ls odj-
jlmhth o` 1>. ]het ls thj pronuat o` thj dukgjredn lts squerj root ?
(E) 8 (G) 7=
(A) 17 (N) Dodj o` thjsj
U.5< ^wo-thlrn o` e posltlvj dukgjr edn750
7:o` lts
rjalproaei erj jquei. ^hj dukgjr ls 6
(E)57
:(G)
:
57
(A)5>>
7:(N)
7:
5>>
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U.73 @ldn e posltlvj dukgjr whjd ldarjesjn gy 5= lsjquei to 03 tlkjs thj rjalproaei o` thj dukgjr.
(E) 1 (G) 53 (A) 5= (N) 73
U.75 E posltlvj dukgjr whjd njarjesjn gy > ls jquei
to 75 tlkjs thj rjalproaei o` thj dukgjr. ^hj
dukgjr ls6(E) 1 (G) : (A) = (N) 6 : 6 0 edn thjlr
evjremj ls 7:. ^hj iermjst dukgjr ls 6
(E) 13 (G) 17 (A) 10 (N) >7
U.70 ^hrjj dukgjrs erj ld thj retlo 1 6 > 6 0 edn thjlr
pronuat ls 5>. ^hj iermjst o` thjsj dukgjr ls 6
(E) 0 (G) 57
(A) 58 (N) Dodj o` thjsj
U.7= ^wo dukgjrs erj suah thet thj squerj o` odj ls
7>> ijss thed 8 tlkjs thj squerj o` thj othjr. L`
thj dukgjr gj ld retlo 1 6 > thj dukgjr erj6
(E) 0, 8 (G) 6 =. L` jeah ls ldarjesjn gy >, thj retlo
gjaokjs 1 6 :. ^hj iermjr dukgjr ls 6
(E) 10 (G) >8
(A) :0 (N) 0>
U.7< ^hj suk o` thrjj dukgjrs ls 70>. L` thj `lrst
dukgjr gj twlaj thj sjaodn edn thlrn dukgjr gj
odj-thlrn o` thj `lrst, thjd thj sjaodn dukgjr ls 6
(E) >8 (G) :>
(A) =7 (N) 8>
U.13 ^hj suk o` two dukgjrs ls 77. @lvj tlkjs odj
dukgjr ls jquei to 0 tlkjs thj othjr. ^hj glmmjr
o` thj two dukgjrs ls 6
(E) 53 (G) 57
(A) 5: (N) 50
U.15 Odj-`l`th o` e dukgjr ls jquei to8: o` edothjr
dukgjr. L` 1: ls ennjn to thj `lrst dukgjr, lt
gjaokjs `our tlkjs o` thj sjaodn dukgjr. ^hj
sjaodn dukgjr ls6
(E) 7: (G) >3
(A) =3 (N) 57:
U.17 ^hj suk o` two dukgjrs ls 7: edn thjlr nl``jrjdaj
ls 51, @ldn thjlr pronuat 6
(E) 53> (G) 55>
(A) 15: (N) 17:
U.11 L` thj suk o` two dukgjrs ls 11 edn thjlr
nl``jrjdaj ls 5:, thj skeiijr dukgjr ls 6
(E) < (G) 57
(A) 5: (N) 58
U.1> ^hj suk o` two dukgjrs ls >3 edn thjlr nl``jrjdaj
ls >. ^hj retlo o` thj dukgjrs ls 6
(E) 55 6 < (G) 55 6 58
(A) 75 6 5< (N) 77 6 yjers. L` thjlr
emjs erj ld thj rjspjatlvj retlo o` = 6
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U.1= ^hj retlo gjtwjjd thj prjsjdt emjs o` S edn U
ls 0 6 =. L` U ls > yjers oin thed S, whet wlii gj
thj retlo o` thj emjs o` S edn U e`tjr > yjers?
(E) 1 6 > (G) 1 6 :
(A) > 6 1 (N) Dodj o` thjsj
U.18 ^hj retlo gjtwjjd thj prjsjdt emjs o` S edn U
ls : 6 = rjspjatlvjiy. L` thj nl``jrjdaj gjtwjjd Us
prjsjdt emj edn Ss emj e`tjr 0 yjers ls 7, whet
ls thj totei o` Ss edn Us prjsjdt emjs ?
(E) >8 yjers (G) :7 yjers
(A) :0 yjers (N) Dodj o` thjsj
U.1< Et prjsjdt, thj retlo gjtwjjd thj emjs o` Erud
edn Njjpeb ls > 6 1. E`tjr 0 yjers, Eruds emj wlii
gj 70 yjers. ]het ls thj emj o` Njjpeb et prjsjdt?
(E) 57 yjers (G) 5: yjers
(A) 53 Srjsjdt emjs o` X edn \ erj ld thj retlo : 6 0
rjspjatlvjiy. Qjvjd yjers hjdaj thls retlo wlii gj
gjaokj 0 6 = rjspjatlvjiy. ]het ls Xs prjsjdt
emj ld yjers ?
(E) 1: (G) >7
(A) >< (N) Aeddot gj njtjrkldn
U.>5 Srjsjdt emjs o` Qekjjr edn Ededn erj ld thj
retlo o` : 6 > rjspjatlvjiy. ^hrjj yjers hjdaj, thj
retlo o` thjlr emjs wlii gjaokj 55 6 < rjsjpjatlvjiy.
]het ls Ededns prjsjdt emj ld yjers?
(E) 7> (G) 7=
(A) >3 (N) Aeddot gj njtjrkldn
U.>7 Qlx yjers emo, thj retlo o` thj emjs o` Budei edn
Qemer wes 0 6 :. @our yjers hjdaj, thj retlo o`
thjlr emjs wlii gj 55 6 53. ]het ls Qemers emj et
prjsjdt ?
(E) 50 yjers (G) 58 yjers
(A) 73 yjers (N) Aeddot gj njtjrkldn
U.>1 ^hj totei o` thj emjs o` Feyedt, Srjk edn Qeredsh
ls . ]het ls thj prjsjdt emj o` Qeredsh?
(E) 7> yjers (G) 17 yjers
(A) 1> yjers (N) 18 yjers
U.>> ^hj retlo o` thj prjsjdt emjs o` two grothjrs ls
5 6 7 edn : yjers geab, thj retlo wes 5 6 1. ]het
wlii gj thj retlo o` thjlr emjs e`tjr : yjers ?
(E) 5 6 > (G) 7 6 1
(A) 1 6 : (N) : 6 0
U.>: Hltjsh ls >3 yjers oin edn Woddlj ls 03 yjers oin.
How kedy yjers emo wes thj retlo o` thjlr emjs
1 6 : ?
(E) : yjers (G) 53 yjers
(A) 73 yjers (N) 1= yjers
U.>0 ^hj retlo o` thj `ethjrs emj to hls sods emj ls
= 6 1. ^hj pronuat o` thjlr emjs ls =:0. ^hj retlo
o` thjlr emjs e`tjr 0 yjers wlii gj 6
(E) : 6 7 (G) 7 6 5
(A) 55 6 = (N) 51 6 = ^hj p rj sj dt e mj s o ` t hrjj p jrso ds e rj l d
proportlods > 6 = 6 : (N) Dodj o` thjsj
U.>8 ^hj retlo o` thj emjs o` e ked edn hls wl`j ls
> 6 1. E`tjr > yjers, thls retlo wlii gj < 6 =. L` et
thj tlkj o` kerrlemj, thj retlo wes : 6 1, thjd how
kedy yjers emo wjrj thjy kerrljn ?
(E) 8 yjers (G) 53 yjers
(A) 57 yjers (N) 5: yjers
U.>< ^hj retlo gjtwjjd thj sahooi emjs o` Djjiek
edn Qheed ls : 6 0 rjspjatlvjiy. L` thj retlo
gjtwjjd thj odj-thlrn emj o` Djjiek edn hei` o`
Qheeds emj ls : 6 yjers emo edn Gs emj > yjers hjdaj 5 6 5.
]het ls thj retlo gjtwjjd Es emj > yjers hjdaj
edn Gs emj > yjers emo?
(E) 5 6 1 (G) 7 6 5
(A) 1 6 5 (N) > 6 5
U.:5 ^jd yjers emo, E wes hei` o` G ld emj. L` thj retlo
o` thjlr prjsjdt emjs ls 1 6 >, whet wlii gj thj
totei o` thjlr prjsjdt emjs ?
(E) 73 yjers (G) 13 yjers
(A) >: yjers (N) Dodj o` thjsj
U.:7 E ls two yjers oinjr thed G who ls twlaj es oin
es A. L` thj totei o` thj emjs o` E, G edn A gj
7=, thjd how oin ls G ?
(E) = (G) 8
(A) < (N) 53
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U.:1 E ked ls 7> yjers oinjr thed hls sod. Ld two
yjers, hls emj wlii gj twlaj thj emj o` hls sod.
^hj prjsjdt emj o` thj sod ls6
(E) 5> (G) 58 yjers
(A) 73 yjers (N) 77 yjers
U.:> Jlmhtjjd yjers emo, e `ethjr wes thrjj tlkjs es
oin es hls sod. ^hjd thj suk o` thj prjsjdt emjs
o` thj sod edn thj `ethjr ls6
(E) :> (G) =7
(A) 53: (N) 538
U.:: E pjrsods prjsjdt emj ls two-`l th o` thj emj o`
hls kothjr. E`tjr 8 yjers, hj wlii gj odj-hei` o`
thj emj o` hls kothjr. How oin ls thj kothjr et
prjsjdt?
(E) 17 yjers (G) 10 yjers
(A) >3 yjers (N) >8 yjers
U.:0 ^edyes mredn`ethjr wes 8 tlkjs oinjr to hjr
50 yjers emo. Hj wouin gj 1 tlkjs o` hjr emj
8 yjers `rok dow. Jlmht yjers emo, whet wes thj
retlo o` ^edyes emj to thet o` hjr mredn`ethjr?
(E) 5 6 7
(G) 5 6 :
(A) 1 6 8
(N) Dodj o` thjsj
U.:= ^hj emj o` `ethjr 53 yjers emo wes thrlaj thj emj
o` hls sod. ^jd yjers hjdaj, `ethjrs emj wlii gj
twlaj thet o` hls sod. ^hj retlo o` thjlr prjsjdt
emjs ls 6
(E) :6 7 (G) = 6 1
(A) < 6 7 (N) 51 6 >
U.:8 @our yjers emo, thj `ethjrs emj wes thrjj tlkjs
thj emj o` hls sod. ^hj totei o` thj emjs o` thj
`ethjr edn thj sod e`tjr `our yjers, wlii gj
0> yjers. ]het ls thj `ethjrs emj et prjsjdt?
(E) 17 yjers (G) 10 yjers
(A) >> yjers (N) Dodj o` thjsj
U.:< Odj yjer emo, Sroklie wes `our tlkjs es oin es
hjr neumhtjr Qebshl. Qlx yjers hjdaj, Sroklie
emj wlii jxajjn hjr neumhtjr emj gy < yjer thj
retlo o` thj prjsjdt emjs o` Sroklie edn hjr
neumthjr ls6
(E) < 6 7 (G) 55 6 1
(A) 57 6 : (N) 51 6 >
U.03 ^hj suk o` thj prjsjdt emjs o` e `ethjr edn hls
sod ls 03 yjers. Qlx yjers emo, `ethjrs emj wes
`lvj tlkjs thj emj o` thj sod. E`tjr 0 yjers, sods
emj wlii gj6
(E) 57 yjers (G) 5> yjers
(A) 58 yjers (N) 73 yjers
EDQ]JW BJ\
U.Do 5 7 1 > : 0 = 8 < 53 55 57 51 5> 5: 50 5= 58 5< 73
Eds. A G N A A A E A N E N A A G N G G E E E
U.Do 75 77 71 7> 7: 70 7= 78 7< 13 15 17 11 1> 1: 10 1= 18 1< >3
Eds. A E A G E A E A A G G G E E E N N E G E
U.Do >5 >7 >1 >> >: >0 >= >8 >< :3 :5 :7 :1 :> :: :0 := :8 :< 03
Eds. E E N A G G G A N A N N N N A N G N N N
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Qoi.5: Ijt thj dukgjrs gj x, y edn z. ^hjd,
x + y ; 53 ... (l)
y + z ; 5< ... (ll)
x + z ; 75 ... (lll)
Ennldm (l), (ll) edn (lll),
wj mjt 6 7(x + y + z) ; :3 or (x + y + z) ; 7:.
^hus, x ; (7: 52
z ; (7: 53) ; 5:
Hjdaj, thj rjqulrjn dukgjrs erj 0, >, edn 5:.
Qoi.50 Ijt Wefjjvs prjsjdt emj gj x yjers. ^hjd,
Wefjjvs e`j e`tjr 5: yjers ; (x + 5:) yjers.
Wefjjvs emj : yjers geab ; (x :) yjers.
x + 5: ; : (x :) x + 5: ; :x 7:
>x ; 53 x ; 53.
Hjdaj, Wefjjvs prjsjdt emj ; 53 yjers.
Qoi.5= Ijt thj emj o` thj youdmjr pjrsod gj x yjers.
^hjd, emj o` thj jinjr pjrsod ; (x + 50) yjers.
1(x 0) ; (x + 50 0) 1x 58 ; x + 53
7x ; 78 x ; 5>.
Hjdaj, thjlr prjsjdt emjs erj 5> yjers edn 13
yjers.
Qoi.58 Ijt Edblts emj gj x yjers. ^hjd, Dlbltes emj
; x
7>3yjers.
7 x
7>3 x ; > >83 x7 ; >x
x7 + >x >83 ; 3
(x + 7>) (x 73); 3 x ; 73.
Hjdaj, Dlbltes emj ;
73
7>3yjers ; 57 yjers.
Qoi.5< Ijt thj sods prjsjdt emj gj x yjers. ^hj, `ethjrs
prjsjdt emj ; (1x + 1) yjers.
(1x + 1 + 1) ; 7 (x + 1) + 53
1x + 0 ; 7x + 50 x ; 53.Hjdaj, `ethjrs prjsjdt emj ; (1x + 1)
; (1 53 + 1)yjers ; 11 yjers.
Qoi.73 Ijt sods emj 8 yjers emo gj x yjers. ^hjd,
Wohlts emj 8 yjers emo ; >x yjers.
Qods emj e tjr 8 yjers ; (x + 8) + 8
; (x + 50)yjers.
Wohlts emj e`tjr 8 yjers ; (>x + 8) + 8
; (>x + 50) yjers.
7 (x + 50) ; >x + 50 7x ; 50 x ; 8.Hjdaj, sods prjsjdt emj ; (x + 8) ; 50 yjers.
Wohlts prjsjdt emj ; (>x + 8) ; >3 yjers.
Qoi.75 Ijt Meurevs edn Qeahlds emjs odj yjers emo gj
0x edn =x yjers rjspjatlvjiy. ^hjd, Meurevs emj
> yjers hjdaj ; (0x + 5) + > ; (0x + :) yjers.
Qeahlds emj > yjers hjdaj ; (=x + 5) + > ; (=x
+ :) yjers.
:x=
:x0
;
8
= 8(0x + :) ; =(=x + :)
>8x + >3 ; >8
8x ; 0> x ; 8.
Hjdaj, Egheys `ethjrs prjsjdt emj ; (:x + 53)
; :3 yjers.
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Qoi.5 Ijt thj dukgjr gj x. ^hjd, x x:
1; :3
x ;
7
::3; 57:.
Qoi.7 Ijt thj dukgjr x. ^hjd,0
>x; 8x > ; >8
x > ; >8 x ; :7.
:
7x;
:
7:7;
:
:3; 53.
Qoi.1 Ijt thj dukgjr gj x. ^hjd,1
5o`
>
5o` x ; 5:
x ; 5: 57 ; 583.
Qo,rjqulrjn dukgjr ;
583
53
1; :>.
Qoi.> Ijt thj dukgjr gj x. ^hjd, 1(7x +
1x
1
5x ; 03
57
x:; 03 x ;
:
5703; 5>>.
Qoi.0 Ijt thj dukgjr gj x. ^hjd,
x 7> ;=
>x x
=
>x ; 7>
=
x ; 7>
x ;
1
=7>; :0.
Quk o` thj nlmlts ; (: + 0) ; 55.
Qoi.= Ijt thj dukgjr gj x. ^hjd, 5:x x ; 5x ; 5.
Qoi.8 Ijt thj dukgjr gj x. ^hjd,>
x; x 75
x ; >x 8> 1x ; 8> x ; 78.
Qoi.< Ijt thj dukjr gj x. ^hjd,
>x
:
5;
53x
>
5
73
x; 5> x ; 5> 73 ; 783.
Qoi.53 Ijt thj iermjr dukgjr gj x.
^hjd, x 57 ; 73% o` x x :x ; 57
:
x>; 57 x ;
>
:57; 5:.
Qoi.55 Ijt thj dukgjr gj x. ^hjd,=
5x
55
5x ; 533
==
x>;533 x ;
>
==33; 5
0x ; 7> x ; >.
Qoi.5> Ijt thj dukgjr gj x.
^hjd,1
7x :3 ;
>
5x + >3
1
7x
>
5x ; x ; x + :3
1x7 :x :3 ; 3 (1x + 53) (x :) ; 3 x ; :.
Hldts & Qoiutlod # 7
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Qoi.58 Ijt thj dukgjr gj x. ^hjd, x +x
5;
8
1>
x
5x 7 ;
8
1> 8x7 1>x + 8 ; 3
>x
7
5=x + > ; 3
(>x 5) (x >) ; 3 x ; >.
.dodetureielsxes,
>
5xdjmijatldm
Wjqulrjn dukgjr ; > > ; > 7 ; 8.
Qoi.5< Ijt thj dukgjr gj x.
^hjd,1
7x ;
750
7:
x
5x7 ;
750
7:
7
1;
5>>
7:
x ;5>>
7:;
57
:.
Qoi.73 Ijt thj dukgjr gj x.
^hjd, x + 5= ;x
03 x7 + 5=x 03 ; 3
(x + 73) (x 1) ; 3 x ; 1.
Qoi.75 Ijt thj dukgjr gj x.
^hjd, x > ;x
75 x7 >x 75 ; 3
(x =) (x + 1) ; 3 x ; =.
Qoi.77 Ijt thj dukgjr gj x. ^hjd, x +
x
5; 1
x
5x
x
5x7 ; 1
x
5x7
x7 + 5 ; 1x7 1 7x7 ; > x7 ; 7
x ; 7 .
Qoi.71 Ijt thj dukgjr gj e edn g. ^hjd, eg ; 5=
e ; 5 edn g ; 5=.
Qo, 7e
5+ 7g
5; 77
77
ge
ge ; 7
77
)5=5(
)5=(5
;
78
; 7:
:
0
17
:x
7
:+ 1 ; 7:
:
0; 13
7
x
:=
7
x
01
x ;
01;
7
=; 1
7
5.
Qoi.7: Ijt t hj d uk gj rs g j > x, : x e dn 0 x. ^hj d,
1x0x:x> ; 7: :x ; 7: x ; :.
Iermjst dukgjr ; 0x ; 13.
Qoi.70 Ijt thj dukgjrs gj 1x, >x edn 0x.
^hjd, 1x >x 0x ; 5> =7x1 ; 5>
x1 ; 7= x ; 1.
Iermjst dukgjr 0x ; 58.
Qoi.7= Ijt thj dukgjrs gj 1x edn >x. ^hjd,
(>x)7 ; 8 (1x7) 77> 50x7 =7x7 77>
:0x
x7
; > x ; 7.Qo, thj dukgjrs erj 0 edn 8
Qoi.78 Ijt thj dukgjr gj >x edn =x.
^hjd,>x=
>x>
;
:
1
:(>x + >) ; 1 (=x + >) x ; 8.
Iermjr dukgjr ; =x ; :0.
Qoi.7< Ijt thj sjaodn dukgjr gj x. ^hjd, `lrst dukgjr
; 7x edn thlrn dukgjr ; 1
x7
7x + x +1
x7; 70>
1
x55; 70>
x ;
55
170>; =7.
Qoi.13 Ijt thj dukgjrs gj x edn (77 x).
^hjd, :x ; 0 (77 x) 55x ; 517 x ; 57.Qo, thj dukgjrs erj 57 edn 53.
Qoi.15 Ijt thj dukgjrs gj x edn y. ^hjd, x:
5; y
8
:
y ; x7:
8.
Dow, x + 1: ; >yx + 1: ; x7:
17 x
7:
=; 1:
x ;
=
7:1:; 57:.
Qjaodn dukgjr ; y ; x7:
8;
57:
7:
8; >3.
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Qoi.17 Ijt thj dukgjrs gj x edn y. ^hjd, x + y ; 7:
edn x y ; 51.
>xy ; (x + y)7 (x y)7 ; (7:)7 (51)7
; 07: 50< ; >:0 xy ; 55>.
Qoi.11 Ijt thj dukgjrs gj x edn y.
^hjd, x + y ; 11 ....(l) edn x y ; 5: ....(ll)
Qoivldm (l) edn (ll), wj mjt 6 x ; 7> , y ;
>3; 53 (x + y) ; 53 (x y)
x ; >. Wjqulrjn retlo ; (0x + >) 6 (=x + >) ; 78 6 17
; = 6 8.
Qoi.18 Ijt thj prjsjdt emjs o` S edn U gj :x yjers edn
=x yjers rjspjatlvjiy.
^hjd, =x (:x + 0) ; 7 7x ; 8 x ; >. Wjqulrjn suk ; :x + =x ; 57x ; >8 yjers.
Qoi.1< Ijt thj prjsjdt emjs o` Erud edn Njjpeb gj >x
yjers edn 1x yjers rjspjatlvjiy.
^hjd, >x + 0 ; 70 >x ; 73 x ; :. Njjpebs emj ; 1x ; 5: yjers.
Qoi.>3 Ijt thj prjsjdt emjs o` X edn \ gj :x yjers edn
0x yjers rjspjatlvjiy.
^hjd,=x0
=x:
;
=
0 =(:x + =) ; 0 (0x + =)
x ; =. Xs prjsjdt emj ; :x ; 1: yjers.
Qoi.>5 Ijt thj prjsjdt emjs o` Qekjjr edn Ededn gj :x
yjers edn >x yjers rjspjatlvjiy.
^hjd,1x>
1x:
;
x ; 7> yjers.
Qoi.>7 Ijt thj emjs o` Budei edn Qemer 0 yjers emo gj
0x edn :x yjers rjspjatlvjiy.
^hjd,>)0x:(
>)0x0(
;
53
55 53(0x + 53)
; 55(:x +53) :x ; 53 x ; 7. Qemers prjsjdt emj ; (:x + 0) ; 50 yjers.
Qoi.>1 Ijt thj emjs o` Feyedt, Srjk edn Qeredsh 53
yjers emo gj 7x, 1x edn >x yjers rjspjatlvjiy.
^hjd, (7x + 53) + (1x + 53) + (>x + 53) ; > Ijt thj prjsjdt emjs o` thj two grothjrs gj x
yjers edn 7x yjers rjspjatlvjiy.
^hjd,:x7
:x;
1
51(x :) ; (7x ):x ;53.
Wjqulrjn retlo ; (x + :) 6 (7x + :) ; 5: 6 7:; 1 6 :
Qoi.>: Qupposj, thj retlo wes 1 6 :, x yjers emo.
^hjd,x03x>3
;15
:(>3 x) ; 1 (03 x)
7x ; 73 x ; 53.
Qoi.>0 Ijt thj prjsjdt emjs o` thj `ethjr edn sod gj =x
edn 1x yjers rjspjatlvjiy.
^hjd, =x 1x ; =:0 75x7 ; =:0 x7 ; 10 x ; 0.
Wjqulrjn retlo ; (=x + 0) 6 (1x + 0) ; >8 6 7>; 7 6 5
Qoi.>= Ijt thjlr prjsjdt emjs gj >x, =x edn x 8) + (=x 8) + ( ^hjlr prjsjdt emjs erj 50 yjers, 78 yjers edn10 yjers rjspjatlvjiy.
Qoi.>8 Ijt thj prjsjdt emjs o` thj ked edn hls wl j gj
>x edn 1x yjers rjspjatlvjiy.
^hjd,>x1
>x>
;
=
< =(>x + >) ; )
x ; 8.Qo, thjlr prjsjdt emjs erj 17 yjers edn 7> yjers
rjspjatlvjiy.
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Qupposj thjy wjrj kerrljn z yjers emo.
^hjd,z7>
z17;
1
:; 1(17 z) ; :(7> z)
7z ; 7> z ; 57.
Qoi.>< Ijt thj sahooi emjs o` Djjiek edn Qheed gj :x
edn 0x yjers rjspjatlvjiy. ^hjd,
x07
5
x:1
5
;
x:
;
55 :x > ; 1x + >
7x ; 8 x ; >.Wjqulrjn retlo ; (:x + >)6 (1x >)
; 7> 6 8 ; 1 6 5.
Qoi.:5 Ijt thj emjs o` E edn G 53 yjers emo gj x edn
7x yjers rjspjatlvjiy.
^hjd,53x7
53x
;
>
1 >(x + 53) ; 1(7x + 53)
7x ; 53 x ; :. Quk o` thjlr prjsjdt emjs
; (x + 53) + (7x + 53) ; (1x + 73) ; 1: yjers.
Qoi.:7 Ijt As emj gj x yjers . ^hjd, Gs emj ; 7x yjers,
Es emj ; (7x + 7) yjers.
(7x + 7) + 7x + x ; 7= :x ; 7: x ; :.Hjdaj, Gs emj ; 7x ; 53 yjers.
Qoi.:1 Ijt thj sods prjsjdt emj gj x yjers. ^hjd, keds
prjsjdt emj ; (x + 7>) yjers.
(x + 7>) + 7 ; 7(x + 7) x + 70 ; 7x + > x ; 77.
Qoi.:> Ijt thj prjsjdt emjs o` thj `ethjr edn sod gj 7x
edn x yjers rjspjatlvjiy.^hjd, (7x 58) ; 1(x 58) x ; 10. Wjqulrjn suk ; (7x + x) ; 1x ; 538 yjers.
Qoi.:: Ijt thj kothjrs prjsjdt emj gj x yjers.^hjd,
thj pjrsods prjsjdt emj ;
x
:
7yjers
8x
:
7;
7
5(x + 8)7(7x + >3) ; :(x + 8)
x ; >3.
Qoi.:0 50 yjers emo, ijt ^ ; x yjers edn M ; 8x yjers.
E`tjr 8 yjers `rok dow, ^ ; (x + 50 + 8) yjers edn
M ; (8x + 50 + 8) yjers.
8x + 7> ; 1 (x + 7>) :x ; >8.
8 yjers emo,M^
;8x8
8x ;
8:
>88
8:
>8
;>7>88
;:1
55.
Qoi.:= Ijt thj emjs o` `ethjr edn sod 53 yjers emo gj
1x edn x yjers rjspjatlvjiy.
^hjd, (1x + 53) + 53 ; 7 R(x + 53) + 53[1x +73 ; 7x + >3 x ; 73.Wjqulrjn rtelo ; (1x + 53) 6 (x + 53)
=3 6 13 ; = 6 1.
Qoi.:8 Ijt thj emjs o` `ethjr edn sod > yjers emo gj 1x
edn x yjers rjspjatlvjiy.
^hjd, R(1x + >) + >[ + R(x + >) + >[ >x ; >8 x ; 57.
@ethjrs prjsjdt emj ; 1x ; 10 yjers.Qoi.:< Ijt emjs o` Sroklie edn Qebshl 5 yjer emo gj >x
edn x yjers rjspjatlvjiy.
^hjd, R(>x + 5) + 0[ R(x + 5) + 0[ ; .
Qoi.03 Ijt thj prjsjdt emjs o` sod edn `ethjr gj x edn(03 x) yjers rjspjatlvjiy.
^hjd, (03 x) 0 ; : (x 0) :> x; :x 13 0x ; 8> x ; 5>.
Qods emj e`tjr 0 yjer ; (x + 0) ; 73 yjers.