# Math Help - implicit differentiation

1. ## implicit differentiation

dy/dx when $-xy^2 + 10x^2y = -x + 2$

i got

(10x^2 - 2yx + 10xy + 1) / y^2 = dy/dx

can some one please check if this is right

2. Originally Posted by helmszee
dy/dx when $-xy^2 + 10x^2y = -x + 2$

i got

(10x^2 - 2yx + 10xy + 1) / y^2 = dy/dx

can some one please check if this is right
that's not what i got, so i guess you're wrong

3. ....wanna let me know wat u get or how u got it then plz

4. ok, i'll post. see if you can spot a mistake, if any. i'm kind of tired and too lazy to check through it myself, it will be good practice for you

$-xy^2 + 10x^2 y = -x + 2$

differentiating implicitly we get

$-y^2 - 2xy~\frac {dy}{dx} + 20xy + 10x^2~\frac {dy}{dx} = -1$

$\Rightarrow \frac {dy}{dx} \left( 10x^2 - 2xy \right) = y^2 - 20xy - 1$

$\Rightarrow \frac {dy}{dx} = \frac {y^2 - 20xy - 1}{10x^2 - 2xy}$

everything good?