1.	If x and y are acute angles such that sin x = and sin y = , what is the value of cos (x - y)?
		A.		B.
		C.		D.
		Hint
	2.	Complete the identity ______________.
		A.	-cos A	B.	cos A
		C.	-sin A	D.	sin A
		Hint
	3.	Use the sum or difference identity for tangent to find the exact value of tan 165°.
		A.	-	B.	1
		C.		D.	- 2
		Hint
	4.	Find the value of cos (x - y) if 0 < x < , 0 < y < , sin x = , and cos y = .
		A.		B.
		C.		D.
		Hint
	5.	If angles x and y are between 0° and 180° such that cos x = - and cos y = , what is the value of sin (x + y)?
		A.		B.
		C.		D.
		Hint