Answer is: option3
(C)Solution:
Trapezoidal Rule Behavior:
- Trapezoid sums underapproximate when the function is concave down (∩ shape).
- Trapezoid sums overapproximate when the function is concave up (∪ shape).
Right Riemann Sum Behavior:
- Right Riemann sums overapproximate when the function is increasing.
- Right Riemann sums underapproximate when the function is decreasing.
So we need a function that is:
- Concave down
- Increasing
- (A) Decreasing and concave down → Right Riemann sum would underapproximate. ❌
- (B) Increasing and concave up → Trapezoid would overapproximate. ❌
- (C) Increasing and concave down → ✔ This matches both clues.
- (D) Decreasing and concave down → Right Riemann underapproximates. ❌
Option C