How do you find the derivative of the function: (arctan(6x^2 +5))^2?

1 Answer
Jan 23, 2016

(24xarctan(6x^2+5))/((6x^2+5)^2+1)

Explanation:

This will require a little chain rule.

The first issue is the second power, which can be dealt with as such: d/dx[u^2]=2u*u'. We know that u=arctan(6x^2+5), so

f'(x)=2arctan(6x^2+5)d/dx[arctan(6x^2+5)]

Now, we must deal with the arctan function, which uses the rule d/dx[arctan(u)]=(u')/(u^2+1), and we have u=6x^2+5, giving us

f'(x)=2arctan(6x^2+5)*(d/dx[6x^2+5])/((6x^2+5)^2+1)

Simplify:

f'(x)=(2arctan(6x^2+5)*12x)/((6x^2+5)^2+1)

f'(x)=(24xarctan(6x^2+5))/((6x^2+5)^2+1)