​ If =where a/b is a rational number in its lowest form, then correct options is/are a) a-b=3 b) a+b=11 c)a+b=10 d) a-b=4 ​

Question

If \(\sum_{n=1}^{\infty}\cot ^{-1}(\frac{n^2}{8})\)=\(\frac{a}{b}\pi\) where a/b is a rational number in its lowest form, then correct options is/are

a) a-b=3

b) a+b=11

c)a+b=10

d) a-b=4

Answer 1

Answer: a) a-b=3