Jika y = x/x²+1. hasil dari dy/dx

y = x/(x² +1)

u = x
u' = 1

v = x² + 1
v' = 2x

y =  u/v
y' = (u'v - uv')/(v²)

y' = {  1(x² + 1) - x(2x) } / (x² +1)²
y' = { x² + 1 - 2x² } / (x² + 1 )²
y' = (1 - x² )/ (x² + 1)²