If `tan^(-1)x+tan^(-1)y=pi/4,`then write the value of `x+y+x ydot`

1.	If `tan^(-1)x+tan^(-1)y=pi/4,`then write the value of `x+y+x ydot`
Answer» `tan^-1 x + tan^-1 y = pi/4` `tan^-1((x+y)/(1-xy)) = pi/4` `(x+y)/(1-xy) = tan (pi/4)` `(x+y)/(1-xy) = 1` `x+y = 1-xy` `x+y+xy= 1` Answer

Discussion

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If `tan^(-1)x+tan^(-1)y=pi/4,`then write the value of `x+y+x ydot`