Derivative of x² + 3x - 2

Published on October 13, 2024

Calculus

Learn how to find the derivative of the function f(x) = x² + 3x - 2 using the power rule, constant multiple rule, and sum/difference rule. The derivative is f'(x) = 2x + 3.

Question

Find the derivative of f(x) = x² + 3x - 2

Answer

Let’s find the derivative of f(x) = x² + 3x - 2 step-by-step.
1. Power Rule:
  • The power rule states that the derivative of x^n is nx^(n-1).
2. Constant Multiple Rule:
  • The constant multiple rule states that the derivative of a constant times a function is equal to the constant times the derivative of the function.
3. Sum/Difference Rule:
  • The sum/difference rule states that the derivative of a sum or difference of terms is the sum or difference of the derivatives of those terms.
Applying the Rules:
  • Term 1 (x²):
    • Using the power rule, the derivative of x² is 2x^(2-1) = 2x.
  • Term 2 (3x):
    • Using the constant multiple rule, we can factor out the constant 3: 3 * (d/dx)(x).
    • The derivative of x is 1, so the derivative of 3x is 3 * 1 = 3.
  • Term 3 (-2):
    • The derivative of a constant is always 0.
Putting it Together:
The derivative of f(x) = x² + 3x - 2 is the sum of the derivatives of each term:
f’(x) = 2x + 3 + 0
Therefore, the derivative of f(x) = x² + 3x - 2 is:
f’(x) = 2x + 3