December 13th copyright2009merrydavidson

Help each other on HW ?’s

How can I memorize these?

Numerator one less than denominator

Numerator one more than denominator

Add N & D QII to get this numerator

You have to memorize this quadrant! BUT 60 has 3 in denominator and 30 has 6 in denominator

Angles are labeled with:Greek letters

ORUpper case letters

A, B, C, etc.

, ,

Angles….Put definitions on back of plate.

Acute:Obtuse:Right:Quadrantal:Complementary:

Supplementary:

Between 0o and 90o

Between 90o and 180o

90o

Terminal side on x or y axes

Sum of 2 angles = 90o or pi/2 radians

Sum or 2 angles = 180o or pi radians

1 R = 180o

R

1 o = R 180o

1 radian is approximately 57.3o

Mark 1R, 2R = 115o, 3R = 172o,

4R = 229o, 5R = 286o, and 6R = 344o on your paper plate.

Converting from degree to radian measure

Multiply by:

1) 84___

Converting from degree to radian measure

Multiply by:

2) 200

Converting from radian to degree measure

Multiply by:

3) 6 radians________

Converting from radian to degree measure

Multiply by:

4) 17 radians 6

Arc Length

360 2 (2 )o

central arclengthor circumference r

A circle has a radius of 4 inches. Find the length of the arc intercepted by a central angle of 240o.

Area of a Sector

2

sec360 2 ( )o

central areaof toror areaofcircle r

A sprinkler on a golf course fairway is set to spray water over a distance of 70 feet and rotates through an angle of 120o.

Find the area of the fairway watered by the sprinkler.

Finding complementary and supplementary angles

52o C: S:

125o C: S:

C: S:

C: S:

4R

56R

Homework: WS 6-2