Find dydxin the following questions:
y=sin−1(2x1+x2)
Given, y=sin−1(2x1+x2)
putting θ=tan−1x i.e.,x=tan θ
Then, y=sin−1(2tant θ1+tan2θ)=sin−1(sin 2θ)=2θ=2tant−1x [∵ sin 2θ=2tantθ1+tan2θ]
Differentiating both sides w.r.t. x, we get
dydx=ddx(2tan−1)
dydx=2.11+x2=21+x2 [∵ ddxtan−1x=11+x2]