Question

Find the derivatives of 5cosx-3sinx

Answer 1

$let \: \: y = 5cosx - 3sinx \\ \frac{dy}{dx} = 5 \frac{d}{dx} cosx - 3 \frac{d}{dx} sinx \\ = 5( - sinx) - 3cosx \\ = - 5sinx - 3cosx$