# How do you find the derivative of 4x/(4+x^2)?

$4 \frac{1. \left(4 + {x}^{2}\right) - x \left(2 x\right)}{4 + {x}^{2}} ^ 2$
= $4 \frac{4 - {x}^{2}}{4 + {x}^{2}} ^ 2$