Posted by Mike on .
URGENT, Please answer this question:
give the value of:
Tan(Arctan x+1/x1+Arctan x1/x)

Trig 
Reiny,
let arctan((x+1)/(x1)) = A or tanA = (x+1)/(x1)
let arctan((x1)/x) = B or tanB = (x1)/x
then Tan(Arctan x+1/x1+Arctan x1/x)
= tan(A+B)
= (tanA + tanB)/(1tanAtanB)
= [ (x+1)/(x1) + (x1)/x ] / [1  (x+1)/(x1)(x1)/x ]
= ....
= (2x^2  x + 1)/(1x)
check my algebra