Question

Find the derivative of the trigonometric function using the Chain Rule.y=cos✓x​

Answer 1

If y = cos(√x), then by the chain rule

dy/dx = d/dx [cos(√x)]

dy/dx = - sin(√x) d/dx [√x]

dy/dx = - sin(√x) (1 / (2√x))

dy/dx = - 1/2 sin(√x) / √x