Question

Sin^2(45+A)+sin^2(45-A)=1
Prove it​

Answer 1

Explanation:

Setting A=45, we see that it is not true. However, you might find the following revealing:

sin2(45+A)=(sin45cosA+cos45sinA)2=12(1+2cosAsinA)

sin2(45−A)=(sin45cosA−cos45sinA)2=12(1−2cosAsinA)

Now, stare.