NTA Abhyas JEE Main2020MathematicsDefinite IntegrationPractice
If ∫ 0 1 e x 2 x - a d x = 0 , then the value of ∫ 0 1 e x 2 d x is equal to
Options
- A1 2 a e - 1
- Ba 2 e - 1
- C1 2 a e + 1
- Da 2 e + 1
Correct answer
A. 1 2 a e - 1
Step-by-step solution
Given, ∫ 0 1 e x 2 x - a d x = 0 ⇒ ∫ 0 1 e x 2 ⋅ x d x = a ∫ 0 1 e x 2 d x Put x 2 = t (in LHS) ⇒ x d x = d t 2 So, 1 2 ∫ 0 1 e t d t = a ∫ 0 1 e x 2 d x 1 2 e - 1 = a ∫ 0 1 e x 2 d x ∫ 0 1 e x 2 d x = 1 2 a e - 1