Question

What is the derivative of `arctan(x^2+1)`?

Answer 1

`(2x)/(1+(x^2+1)^2)`

Explanation:

From the rules, `d/dxtan^(-1)[u(x)]=1/(1+u^2)*(du)/dx`

we get

`d/dxtan^(-1)(x^2+1)=1/(1+(x^2+1)^2)*2x`