Trigonometric Sum Identities — Unit test

Question 1

Which is equivalent to sin-1(0.75)? Round your answer to the nearest hundredth of a radian.

Revolt · Accepted Answer

0.85

Question 2

What is the value of sin(80°)cos(20°) – cos(80°)sin(20°)?

Revolt · Accepted Answer

StartFraction StartRoot 3 EndRoot Over 2 EndFraction

Question 3

Review the proof of .

Revolt · Accepted Answer

step 5

Question 4

Which expression is equivalent to 2cos2?

Revolt · Accepted Answer

1

Question 5

Simplify

Revolt · Accepted Answer

cos(x) + sin(x)

Question 6

Which equation should be used to graph on a calculator?

Revolt · Accepted Answer

mc012-5.jpg

Question 7

Review the steps of the proof of the identity .Step 1: = Step 2: = Step 3: = Step 4: = Step 5:

Revolt · Accepted Answer

step 2

Question 8

Solve the equation over the interval [0, 2].

Revolt · Accepted Answer

StartFraction 5 pi Over 6 EndFraction and StartFraction 11 pi over 6 EndFraction

Question 9

Let cos(2x) – cos(x) = 0, where 0° ≤ x ≤ 180°. What are the possible values for x?

Revolt · Accepted Answer

0° or 120°

Question 10

What are all the exact solutions of on the interval ? Give your answer in radians.

Revolt · Accepted Answer

mc013-6.jpg

Trigonometric Sum Identities — Unit test Answers