Question

What’s the derivative of f(x) = 2x² _x

Answer 1

`\displaystyle f'(x) = 4x - 1`

General Formulas and Concepts:

Calculus

Differentiation

• Derivatives
• Derivative Notation

Derivative Property [Multiplied Constant]:
`\displaystyle (d)/(dx) [cf(x)] = c \cdot f'(x)`

Derivative Property [Addition/Subtraction]:
`\displaystyle (d)/(dx)[f(x) + g(x)] = (d)/(dx)[f(x)] + (d)/(dx)[g(x)]`

Basic Power Rule:

1. f(x) = cxⁿ
2. f’(x) = c·nxⁿ⁻¹

Explanation:

Step 1: Define

Identify

`\displaystyle f(x) = 2x^2 - x`

Step 2: Differentiate

1. Derivative Property [Addition/Subtraction]:
   `\displaystyle f'(x) = (d)/(dx)[2x^2] - (d)/(dx)[x]`
2. Rewrite [Derivative Property - Multiplied Constant]:
   `\displaystyle f'(x) = 2 (d)/(dx)[x^2] - (d)/(dx)[x]`
3. Basic Power Rule:
   `\displaystyle f'(x) = 4x - 1`

Topic: AP Calculus AB/BC (Calculus I/I + II)

Unit: Differentiation