Question

How do you find the derivative of `y=ln(3/x)`?

Answer 1

`(dy)/(dx) = - 1/x`

Explanation:

We have to use the chain rule. Remember that for a function `y(u(x))` that

`(dy)/(dx) = (dy)/(du)(du)/(dx)`

So `u(x) = 3/x implies (du)/(dx) = -3/(x^2)`

`(dy)/(du) = 1/(3/x) = x/3`

`therefore (dy)/(dx) = - 1/x`