AcademyDifferential Calculus

Academy

Higher Derivatives

Level 1 - Calculus topic page in Differential Calculus.

Principle

Higher derivatives repeat the process of differentiation. They measure how rates of change themselves change. For example, the second derivative measures curvature and acceleration.

Notation

\(f''(x)\)
second derivative of f
\(f^{(n)}(x)\)
nth derivative of f
\(\frac{d^2y}{dx^2}\)
second derivative of y with respect to x

The Core Method

Differentiate once to get \(f'\), then differentiate the result to get \(f''\), and continue as needed.

Second derivative
\[f''(x)=\frac{d}{dx}\left(f'(x)\right)\]

Keep notation clear: \(f^2(x)\) means \((f(x))^2\), but \(f''(x)\) means the second derivative.

Worked Cases

Question
For \(f(x)=x^4-3x^2+2\), find \(f''(x)\).
Answer
First differentiate: \(f'(x)=4x^3-6x\). Differentiate again: \(f''(x)=12x^2-6\).

Examples

Question
Find \(f^{(3)}(x)\) for \(f(x)=x^5\).
Answer
Differentiate repeatedly: \(f'(x)=5x^4\), \(f''(x)=20x^3\), and \(f^{(3)}(x)=60x^2\).