How do you differentiate f(x)=sec(4x^5)?

1 Answer
Aug 13, 2017

d/(dx) [sec(4x^5)] = color(blue)(20x^4tan(4x^5)sec(4x^5)

Explanation:

We're asked to find the derivative

d/(dx) [sec(4x^5)]

We can first use the chain rule:

d/(dx) [sec(4x^5)] = d/(du) [secu] (du)/(dx)

where

  • u = 4x^5

  • d/(du) [secu] = tanusecu:

= tan(4x^5)sec(4x^5)d/(dx) [4x^5]

We now use the power rule:

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

where n = 5:

= tan(4x^5)sec(4x^5)5(4x^4)

color(blue)(ulbar(|stackrel(" ")(" "20x^4tan(4x^5)sec(4x^5)" ")|)