# Math Help - Second derivative question

1. ## Second derivative question

I need to find the second derivative of this fuction: F(x)= sqrt(x^4 + 4x). I found the first derivative no problem which is: f'(x)= (2x^3 + 2)/ sqrt(x^4 + 4x). But I am having trouble with the second derivative, can someone show me? Thanks!

2. Originally Posted by tim
I need to find the second derivative of this fuction: F(x)= sqrt(x^4 + 4x). I found the first derivative no problem which is: f'(x)= (2x^3 + 2)/ sqrt(x^4 + 4x). But I am having trouble with the second derivative, can someone show me? Thanks!
$
F''(x) = \frac{6x^2 \sqrt{x^4 + 4x}- \dfrac{(2x^3+2)^2}{\sqrt{x^4+4x}}}{x^4 + 4x}
$