What is the derivative of tan^4 (x)tan4(x)?

1 Answer
Jan 22, 2016

d/dx[tan^4(x)]=4tan^3(x)sec^2(x)ddx[tan4(x)]=4tan3(x)sec2(x)

Explanation:

The overriding issue is the fourth power. You can deal with it through the chain rule:

d/dx[u^4]=4u^3*u'

Here, we have u=tan(x), so

d/dx[tan^4(x)]=4tan^3(x)*d/dx[tan(x)]

Know that d/dx[tan(x)]=sec^2(x), hence

d/dx[tan^4(x)]=4tan^3(x)sec^2(x)