How do you differentiate sin^2(x/6)?

1 Answer
Aug 19, 2015

y^' = 1/3 * sin(x/6) * cos(x/6)

Explanation:

You can differentiate this function

y = sin(x/6)

by using the chain rule twice, once for u_1^2, with u_1 = sin(x/6), and once for sinu_2, with u_2 = x/6.

Your target derivative will be

d/dx(y) = d/(du_1)(u_1^2) * d/dx(u_1), with

d/dxu_1 = d/(du_2) * sinu_2 * d/dx(u_2)

This will give you

d/dx(u_1) = cosu_2 * d/dx(x/6)

d/dx(sin(x/6)) = cos(x/6) * 1/6

Plug this back into your target derivative to get

y^' = 2u_1 * 1/6 * cos(x/6)

y^' = color(green)(1/3 * sin(x/6) * cos(x/6))