Question

If x + y = xy, then `dy/dx` is ______.

Options

• `y/(x-1)`

• `1/(x-1)`

• `(y-1)/(x-1)`

• `(1-y)/(x-1)`

Answer 1

If x + y = xy, then `dy/dx` is `bbunderline((1-y)/(x-1))`.

Explanation:

⇒ `1+dy/dx=y(1+xdy/dx)`

⇒ `1-y =xdy/dx-dy/dx`

⇒ `1-y=dy/dx(x-1)`

⇒ `dy/dx=(1-y)/(x-1)`