What is the least value of the function f(x) = 2x^2 - 8x - 3 in the interval [0, 5]?
- A. -15
- B. 7
- C. -11
- D. -3
Answer: C. -11
Explanation: f'(x) = 4x - 8 = 0 => x=2. f(2) = 2(4) - 16 - 3 = 8 - 19 = -11. Boundary values: f(0)=-3, f(5)=50-40-3=7. Min is -11.