# Thread: derivative of 1/y

1. ## derivative of 1/y

ok so i have the problem:

If and , find by implicit differentiation.

so i differentiate both sides and get -1/x^2 + -y'/y^2 = 0

then i solve for y' and get y'=-y^2/x^2

this is wrong but i do not know where i went wrong..... im thinking it has to do with the derivative of the 1/y.

could i get some advice please =)

thank you

2. Originally Posted by mybrohshi5
ok so i have the problem:

If and , find by implicit differentiation.

so i differentiate both sides and get -1/x^2 + -y'/y^2 = 0

then i solve for y' and get y'=-y^2/x^2

this is wrong but i do not know where i went wrong..... im thinking it has to do with the derivative of the 1/y.

could i get some advice please =)

thank you
why do you say that $y' = -\frac{y^2}{x^2}$ is wrong?

it's not.

3. you are right, it is right lol. i just must have not used enough decimal places in my answer because my web homework was saying it was incorrect but i just put it in again with a few more decimal places and it is right now =)

thanks for clarifying this for me