Question

What is the derivative of `Tan^-1 (y/x) = 0`?

Answer 1

`dy/dx = 0` provided `x != 0`

Explanation:

`tan^(-1)(y/x)` is only defined if `x != 0`

In which case we have:

`tan^(-1)(y/x) = 0`
`:. y/x = 0`
`:. y=0 => dy/dx = 0`