Question

If f(x) = 4x³ - 3x² + 5, find f"(x).
1. 12x² - 6x
2. 24x - 6
3. 24x
4. None of these

Answer 1

Correct Answer - Option 2 : 24x - 6

Concept:

Formula used: 

If f(x) = xn, then f'(x) = n xn - 1

Calculation:

Given:

f(x) = 4x3 - 3x2 + 5

Differentiation with respect to x, we get

f'(x) = 4 × 3 × x² - 3 × 2 × x 

f'(x) = 12x² - 6x

Again, Differentiation with respect to x

⇒ f"(x) = 24x - 6