`tan^-1(1/3)-tan^-1(4/7)=?`

tan^(-1)(1/7)+tan^(-1)(4/7)+tan^(-1)(9/7)=.........

Find the sum series: tan^-1 (1/3)+tan^-1 (1/7)+tan^-1(1/13)+…to oo

If S=tan^(-1)(1/3)+tan^(-1)(1/7)+tan^(-1)(1/13)+.... to 10 terms. Find tanS

tan^-1 (1/6) + tan^-1 (5/7) = π/4

Prove that: tan^-1 (1/3)+tan^-1 (2/9)+tan^-1 (4/33)+… tooo= pi/4

tan^-1 (1/2) + tan^-1 (1/3) = π/4

PT tan^(-1)(3/4)+tan^(-1)(1/3)=tan^(-1)(13/9)

Prove the following: 4tan^(-1)(1)/(5)-tan^(-1)(1)/(70)+tan^(-1)(1)/(99)=(pi)/(4)2tan^(-1)(1)/(5)+sec^(-1)(5sqrt(2))/(7)+2tan^(-1)(1)/(8)=(pi)/(4)