NTA Abhyas JEE Main2020MathematicsDefinite IntegrationPractice
The value of l i m n → ∞ e 1 n n 2 + 2 e 2 n n 2 + 3 e 3 n n 2 + … + 2 e 2 n is
Options
- Ae 2 - 1
- Be 2 + 1
- C2 e 2 + 1
- D2 e 2 - 1
Correct answer
B. e 2 + 1
Step-by-step solution
Let, I = l i m n → ∞   ∑ r = 1 2 n r n 2 e r n I = l i m n → ∞   ∑ r = 1 2 n r n e r n 1 n I = ∫ 0 2 x e x d x I = x e x 0 2 - ∫ 0 2 e x d x I = 2 e 2 - e 2 - 1 I = e 2 + 1