∑
TestPrep
Magic
Features
Entrance Test
Puzzles
Videos
Practice
Download Free
Features
Entrance Test
Puzzles
Videos
Practice
Download Free
← Back to Test
Problem 18 - Entrance Test
Let f(x) = ∫₀ˣ t sin t dt. Then f'(x) is:
A. x cos x
B. sin x + x cos x
C. x sin x
D. x sin x + cos x
Check Answer
Show Solution
Correct: C
According to the Fundamental Theorem of Calculus, if f(x) = ∫ₐˣ g(t) dt, then f'(x) = g(x). Therefore, if f(x) = ∫₀ˣ t sin t dt, then f'(x) = x sin x.