How to differentiate y= ln^3(cos^2 √(1-x)y=ln3(cos2(1x)?

1 Answer
Aug 11, 2015

(3ln^{2}(cos^{2}(sqrt(1-x)))tan(sqrt(1-x)))/(sqrt(1-x))3ln2(cos2(1x))tan(1x)1x

Explanation:

You have to use the Chain Rule five times:

If y=f(x)=ln^{3}(cos^{2}(sqrt(1-x)))y=f(x)=ln3(cos2(1x)), then

f'(x)=3ln^{2}(cos^{2}(sqrt(1-x))) * d/dx(ln(cos^{2}(sqrt{1-x})))

=3ln^[2}(cos^{2}(sqrt(1-x))) * 1/(cos^{2}(sqrt(1-x))) * d/dx(cos^{2}(sqrt(1-x)))

=(3ln^[2}(cos^{2}(1-x)))/(cos^{2}(sqrt(1-x))) * 2cos(sqrt(1-x)) * d/dx(cos(sqrt(1-x)))

=(6ln^[2}(cos^{2}(1-x)))/(cos(sqrt(1-x))) * (-sin(sqrt(1-x))) * d/dx((1-x)^[1/2})

=-6ln^[2}(cos^[2}(1-x)) tan(sqrt(1-x)) * 1/2 (1-x)^{-1/2} * d/dx(1-x)

=(3ln^{2}(cos^{2}(sqrt(1-x)))tan(sqrt(1-x)))/(sqrt(1-x))