D A N I E L A T K I N S , K E R R Y M I N D I A K , G I N A S C H N E C K E R , K E L L Y T H O R N

Unit 5 – Intro to Trigonometry

Radians!

To Convert…

To convert degrees to radians, multiply degrees by

Practice:

1) 135° = ?

2) -270° = ?

Answers!

1)

2)

To Convert…

To convert radians to degrees, multiply radians by

Practice:

1)

2)

Answers!

1) -90°

2) 810°

Law of Sines

The Law!

Two angles and any side (AAS, ASA)

Two sides and an angle opposite them (SSA the ambiguous case)

Problems!

1)

102.3°a

28.7°

b= 27.4 ft

C

BcA

Problems!

2)

A

BC

38°

63°

15b

a

Problems!

3) C

A B

50 33

132°

Answers!

1) A= 49.0°, c= 55.75, a= 43.06

2) C= 79°, a= 9.41, b= 13.6

3) NO SOLUTION!

Law of Cosines

The Law!

Three sides (SSS)

Two sides and their included angle (SAS)

Problems!

1) B

CA

148

19

Problems

2)

C

a

BA10

15

115°

Answers!

1) A= 22.08°, B= 116.80°, C= 41.12°

2) a= 21.26, B= 39.75°, C= 25.25°

DUN…DUN…DUN!

The Unit Circle!

The Circle!

MEMORIZE THIS!!!

Problems!

1) Sin 60°= ?

2) Sin 30°= ?

3) Cos 45°= ?

4) Cos 135°= ?

5) Tan 45°= ?

6) Tan 210°= ?

Answers!

1) 5) 1

2) 6)

3)

4)