Chain Rule Math Example 4

Follow the full solution, then compare it with the other examples linked below.

Example 4

easy
Find the derivative of f(x)=(5xโˆ’2)3f(x) = (5x - 2)^3.

Solution

  1. 1
    Outer: u3u^3, inner: u=5xโˆ’2u = 5x - 2, inner derivative: 55.
  2. 2
    Chain rule: 3(5xโˆ’2)2โ‹…5=15(5xโˆ’2)23(5x-2)^2 \cdot 5 = 15(5x-2)^2.

Answer

fโ€ฒ(x)=15(5xโˆ’2)2f'(x) = 15(5x - 2)^2
Apply the chain rule: bring down the power, reduce by one, multiply by the derivative of the inner function.

About Chain Rule

The derivative of a composite function f(g(x))f(g(x)) equals fโ€ฒ(g(x))โ‹…gโ€ฒ(x)f'(g(x)) \cdot g'(x): the derivative of the outer function evaluated at the inner, times the derivative of the inner.

Learn more about Chain Rule โ†’

More Chain Rule Examples