Question
Question: The sum of the series\(\frac{1}{1.2} + \frac{1.3}{1.2.3.4} + \frac{1.3.5}{1.2.3.4.5.6} + .....\infty...
The sum of the series1.21+1.2.3.41.3+1.2.3.4.5.61.3.5+.....∞ is.
A
15e
B
e1/2+e
C
e1/2−1
D
e1/2−e
Answer
e1/2−1
Explanation
Solution
The nth term of given series is
loge2
Tn=1⋅2⋅3⋅4…(2n−1)(2n)1⋅2⋅3⋅4….(2n−2)(2n−1)(2n) loge(23)
Tn loge2,loge(32)