Question

If sin 2a + sin 2b = 1/2 and cos 2a + cos2b = 3/2, then cos^2(a-b) is equal to
(A) 3/8
(B) 5/8 [correct answer]
(C) ¾
(D) 5/4
Please give the solution for this question..

Answer 1

Step-by-step explanation:

put sin 2a+ sin 2b and cos 2a + cos 2b formula and take square on both sides and add and take common you get the ans 5/8