[" 7."tan^(-1)(1)=" coooo "?],[qquad [" (A) "(pi)/(4)," (B) "(pi)/(2)]]

Prove that "tan"^(-1)(1)/(5) +"tan"^(-1)(1)/(7) +"tan"^(-1)(1)/(3) +"tan"^(-1)(1)/(8) =(pi)/(4) .

Prove that tan ^ (- 1) (1) / (3) + tan ^ (- 1) (1) / (5) + tan ^ (- 1) (1) / (7) + tan ^ (- 1) (1) / (8) = (pi) / (4)

Prove that: tan^(-1) ""(1)/(7) + tan^(-1) ""(1)/(13) - tan^(-1) ""(2)/(9) =0

2 tan ^(-1) ""(1)/(5)+tan^(-1)"" (1)/(8)= tan ^(-1) ""(4)/(7)

Prove that 2"tan"^(-1)(1)/(2) +"tan"^(-1)(1)/(7) ="tan"^(-1)(31)/(17) .

tan ^(-1) ""(1)/(3) + tan^(-1)""(1)/(7)+tan ^(-1)""(1)/(5)+tan ^(-1)""(1)/(8)=(pi)/(4)

2"tan"^(-1)1/3+"tan"^(-1)1/7=

Prove that tan ^ (- 1) ((1) / (3)) + tan ^ (- 1) ((1) / (7)) + tan ^ (- 1) ((1) / (13)) + ......... + tan ^ (- 1) ((1) / (n ^ (2) + n + 1)) +

Prove that tan^(-1)((1)/(5)) +tan^(-1)((1)/(7)) +tan^(-1)((1)/(3)) +tan^(-1)((1)/(8)) = (pi)/(4) .