NTA Abhyas JEE Main2020MathematicsDefinite IntegrationPractice
If f x satisfies f x + f 3 - x = 3 ∀ x ∈ R , then the value of integral I = ∫ 3 4 9 4 f f x d x is equal to
Options
- A3
- B6
- C9 4
- D9 2
Correct answer
C. 9 4
Step-by-step solution
Applying a + b - x property and adding, we get, 2 I = ∫ 3 4 9 4 f f x + f f 3 - x d x = ∫ 3 4 9 4 f f x + f 3 - f x d x = ∫ 3 4 9 4 f λ + f 3 - λ d x = ∫ 3 4 9 4 3 d x ⇒ 2 I = 3 9 4 - 3 4 ⇒ I = 9 4