# How do you implicitly differentiate  x^2/y + 4y^2 = 36-y+4x?

Nov 29, 2015

Remember to use the chain rule when implicitly differentiating the variable y .

#### Explanation:

Differentiating the equation ...

$2 x {y}^{-} 1 + {x}^{2} \left(- {y}^{-} 2 y '\right) + 8 y y ' = - y ' + 4$

Next, solve for $y '$

$y ' = \frac{4 - 2 x {y}^{-} 1}{8 y - {x}^{2} {y}^{-} 2}$

hope that helped