Question

How do you find the derivative of `1/x+1/y=7`?

Answer 1

`x^-1 + y^-1 = 7`

`-1x^-2 - y^-2dy/dx = 0`

`-y^-2(dy/dx) = 1/x^2`

`dy/dx = (1/x^2)/(-1/y^2)`

`dy/dx= -y^2/x^2`

Hopefully this helps!