If sin-12a1+a2+sin-12b1+b2=2tan-1(x), then x=
a-b1+ab
b1+ab
b1-ab
a+b1-ab
Explanation for the correct option.
Given that, sin-12a1+a2+sin-12b1+b2=2tan-1(x)
We know the identity, 2tan-1a=sin-12a1+a2.
So, we have
2tan-1a+2tan-1b=2tan-1x⇒tan-1a+tan-1b=tan-1x⇒tan-1a+b1-ab=tan-1x⇒x=a+b1-ab
Hence, option D is correct.