Question
Question: f(x) = \(\int _ { 0 } ^ { x } \left( t ^ { 2 } - 1 \right) \cos t d t\), x ∈ (0, 2π).f(x) attains l...
f(x) = ∫0x(t2−1)costdt, x ∈ (0, 2π).f(x) attains local
maximum value at
A
x = π/2
B
x = 1
C
x = 3π/2
D
None
Answer
x = π/2
Explanation
Solution
f '(x) = (x2 – 1) cosx Sign scheme of f '(x) is

clearly x = 2π is the point of local maxima.