Find the value of `4tan^(-1)1/5-tan^(-1)1/(70)+tan^(-1)1/(99)`

Find the value of 4 tan^(-1).(1)/(5) - tan^(-1).(1)/(70) + tan^(-1).(1)/(99)

4tan^(-1)((1)/(5))-tan^(-1)((1)/(70))+tan^(-1)((1)/(99))=pi/4

Find the value of 4tan^(-1)((1)/(5))-tan^(-1)((1)/(239))

Find the value of : 4(2 tan^(-1) . 1/3 +tan^(-1). 1/7)

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)

find out the value of tan^(-1)(5)+tan^(-1)(3)-cot^(-1)((4)/(7))