NTA Abhyas JEE Main2020MathematicsDefinite IntegrationPractice
Let f x be a differentiable function such that ∫ t t 2 x f x d x = 4 3 t 3 - 4 t 3   ∀ t ≥ 0 , then f 1 is equal to
Options
- A4
- B4 3
- C3
- D8 3
Correct answer
D. 8 3
Step-by-step solution
Differentiating both side using Leibnitz rule, we get, t 2 f t 2 ⋅ 2 t − t f t = 4 t 2 − 4 3 Substituting t = 1 , we get, f 1 = 8 3