Answer
$y'=4(x^2/8+x-1/x)^3\times(x/4+1+1/x^2)$
Work Step by Step
Find y and u:
$y=u^4$
$u=x^2/8+x-1/x$
First, find the derivative of y and u. Don't forget to apply chain rule for y':
$y'=4u^3\times u'$
$u'=x/4+1+1/x^2$
Then plug in u and u' into y':
$y'=4(x^2/8+x-1/x)^3\times(x/4+1+1/x^2)$
