Differentiate y=lnsinx-(1/2)sin^(2)x ?

1 Answer
Jun 14, 2017

dy/dx = cotx - sinx cosxdydx=cotxsinxcosx

Explanation:

y=lnsinx - 1/2 sin^2 xy=lnsinx12sin2x

The derivative of the lnln of a function is given by:

d/dx[lnf(x)] = (f'(x))/(f(x))

d/dx(lnsinx) = 1/sinx xx d/dx(sinx) = cosx/sinx=cotx

The derivative of a function
to a power is:

d/dx([f(x)]^n) = n[f(x)]^(n-1) f'(x)

d/dx(1/2sin^2x) = 2(1/2sinx d/dx(sinx)) = sinx cosx

therefore dy/dx = cotx -sinxcosx