The position of a moving car at time is given by , where and c are real numbers greater than 1. Then the average speed of the car over the time interval is attained at the point:
- (A)
- (B)
- (C)✓ Correct
- (D)
Answer: (C)
Solution
The average speed over is . The instantaneous speed is , and setting it equal to the average gives , so . The average speed is attained at the midpoint of the interval.
JEE Main · 2020 · 06 Sep 2020 · Shift 1 · Single correct option