(3x+1)^3/(3x+1)^3 +1 use the chain rule to complete the derivative

Answer 1

if u = 3x+1, we have
y = u^3/(u^3+1)
y' = 3u^2/(u^3+1)^2 u'
= 9(3x+1)^2/((3x+1)^3 + 1)^2

Answer 2

Thank you