NTA Abhyas JEE Main2020MathematicsIndefinite IntegrationPractice
If I n = ∫ x n e 6 x d x , then the expression 6 I 10 + 10 I 9 simplifies to (where, c is the constant of integration)
Options
- Ax 10 e 5 x + c
- Bx 10 e 6 x + c
- Cx 9 e 5 x + c
- Dx 10 e 10 x + c
Correct answer
B. x 10 e 6 x + c
Step-by-step solution
Using integration by parts in I n , we get, I n = ∫ x n ⏟ I e 6 x ⏟ I I d x = x n e 6 x 6 - ∫ n x n - 1 e 6 x 6 d x ⇒ 6 I n = x n e 6 x - n I n - 1 + c ⇒ 6 I n + n I n - 1 = x n e 6 x + c Put n = 10 , 6 I 10 + 10 I 9 = x 10 e 6 x + c