exponents and powers by arjun rastogi

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Page 1: Exponents and powers by arjun rastogi
Page 2: Exponents and powers by arjun rastogi

EXPONENTS

• A quantity representing the power to which

a given number or expression is to be

raised, usually expressed as a raised

symbol beside the number or expression

(e.g. 3 in 23 = 2 × 2 × 2).

Page 3: Exponents and powers by arjun rastogi

• Exponents are shorthand for repeated multiplication of the same thing by itself. For instance, the shorthand for multiplying three copies of the number 5 is shown on the right-hand side of the "equals" sign in (5)(5)(5) =53. The "exponent", being 3 in this example, stands for however many times the value is being multiplied. The thing that's being multiplied, being5 in this example, is called the "base".

General Enquiry

Page 4: Exponents and powers by arjun rastogi

Exponents

35Power

base

exponent

3 3 means that is the exponential

form of t

Example:

he number

125 5 5

.125

53 means 3 factors of 5 or 5 x 5 x 5

Page 5: Exponents and powers by arjun rastogi

The Laws of Exponent

Comes From 3 ideas

• The exponent says how many times to

use the number in a multiplication.

• A negative exponent means divide,

because the opposite of multiplying is

dividing

• A fractional exponent like 1/n means

to take the nth root:

Page 6: Exponents and powers by arjun rastogi

Laws Of Exponent• x1 = x

• x0 = 1

• x-1 = 1/x

• xmxn = xm+n

• xm/xn = xm-n

• (xm)n = xmn

• (xy)n = xnyn

• (x/y)n = xn/yn

• x-n = 1/xn

Page 7: Exponents and powers by arjun rastogi

The Laws of Exponents:

#1: Exponential form: The exponent of a power indicates

how many times the base multiplies itself.

n

n times

x x x x x x x x

3Example: 5 5 5 5

n factors of x

Page 8: Exponents and powers by arjun rastogi

#2: Multiplying Powers: If you are multiplying Powers

with the same base, KEEP the BASE & ADD the EXPONENTS!

m n m nx x x

So, I get it! When you multiply Powers, you add the exponents!

512

2222 93636

Page 9: Exponents and powers by arjun rastogi

#3: Dividing Powers: When dividing Powers with the

same base, KEEP the BASE & SUBTRACT the EXPONENTS!

mm n m n

n

xx x x

x

So, I get it!

When you divide Powers, you subtract the exponents!

16

222

2 426

2

6

Page 10: Exponents and powers by arjun rastogi

#4: Power of a Power: If you are raising a Power to an

exponent, you multiply the exponents!

n

m mnx x

So, when I take a Power to a power, I multiply the exponents

52323 55)5(

Page 11: Exponents and powers by arjun rastogi

#5: Product Law of Exponents: If the product of the

bases is powered by the same exponent, then the result is a

multiplication of individual factors of the product, each powered

by the given exponent.

n n nxy x y

So, when I take a Power of a Product, I apply the exponent to all factors of the product.

222)( baab

Page 12: Exponents and powers by arjun rastogi

#6: Quotient Law of Exponents: If the quotient of the

bases is powered by the same exponent, then the result is both

numerator and denominator , each powered by the given exponent.

n n

n

x x

y y

So, when I take a Power of a Quotient, I apply the exponent to all parts of the quotient.

81

16

3

2

3

24

44

Page 13: Exponents and powers by arjun rastogi

Try these:

523.1

43.2 a

322.3 a

23522.4 ba

22 )3(.5 a

342.6 ts

5

.7t

s

2

5

9

3

3.8

2

4

8

.9rt

st

2

54

85

4

36.10

ba

ba

Page 14: Exponents and powers by arjun rastogi

523.1

43.2 a

322.3 a

23522.4 ba

22 )3(.5 a

342.6 ts

SOLUTIONS

10312a

6323 82 aa

6106104232522 1622 bababa

422293 aa

1263432 tsts

Page 15: Exponents and powers by arjun rastogi

5

.7t

s

2

5

9

3

3.8

2

4

8

.9rt

st

2

54

85

4

3610

ba

ba

SOLUTIONS

62232223 8199 babaab

2

822

4

r

ts

r

st

824 33

5

5

t

s

Page 16: Exponents and powers by arjun rastogi

#7: Negative Law of Exponents: If the base is powered

by the negative exponent, then the base becomes reciprocal with the

positive exponent.

1m

mx

x

So, when I have a Negative Exponent, I switch the base to its reciprocal with a Positive Exponent.

Ha Ha!

If the base with the negative exponent is in the denominator, it moves to the numerator to lose its negative sign!

933

1

125

1

5

15

2

2

3

3

and

Page 17: Exponents and powers by arjun rastogi

#8: Zero Law of Exponents: Any base powered by zero

exponent equals one.

0 1x

1)5(

1

15

0

0

0

a

and

a

and

So zero factors of a base equals 1. That makes sense! Every power has a coefficient of 1.

Page 18: Exponents and powers by arjun rastogi

Try these:

022.1 ba

42.2 yy

15.3 a

72 4.4 ss

4323.5 yx

042.6 ts

Page 19: Exponents and powers by arjun rastogi

SOLUTIONS

022.1 ba

15.3 a

72 4.4 ss

4323.5 yx

042.6 ts

1

5

1

a54s

12

81284

813

y

xyx

1

Page 20: Exponents and powers by arjun rastogi

Presented by

Arjun Rastogi