Multiple Choice
Simplify the expression by using a sum or difference identity.
-cos (13°) cos(87°) + cos(-77°) sin(-87°)
A) cos 100°
B) 1
C) 0
D) sin 100°
Correct Answer:

Verified
Correct Answer:
Verified
Q549: Prove the identity.<br>-<img src="https://d2lvgg3v3hfg70.cloudfront.net/TB8458/.jpg" alt="Prove the identity.
Q550: Find the exact value of the sum.<br>-sin
Q551: Prove the identity.<br>-<img src="https://d2lvgg3v3hfg70.cloudfront.net/TB8458/.jpg" alt="Prove the identity.
Q552: Identify the equation as either an identity
Q553: Find the exact value by using a
Q555: Write in terms of the cofunction of
Q556: Use an appropriate identity to find the
Q557: Find the exact value using a double-angle
Q558: Use odd and even identities to simplify
Q559: Solve the problem.<br>-A block hanging from a