1.	Find the value of sin (x + y) if , sin x = , and sin y = .
		A.		B.
		C.		D.
		Hint
	2.	Use the sum or difference identity for tangent to find the exact value of tan 255°.
		A.		B.
		C.		D.
		Hint
	3.	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
	4.	Use the sum or difference identity for tangent to find the exact value of tan 165°.
		A.		B.	1
		C.	- 2	D.	-
		Hint
	5.	Find the value of cos (x - y) if 0 < x < , 0 < y < , sin x = , and cos y = .
		A.		B.
		C.		D.
		Hint