Solve tan^-1 (1-x/1+x) - 1/2tan^-1 x = 0
tan-1(1-x/1+1.x) = 1/2(tan-1x)
tan-1(1) - tan-1x = 1/2tan-1x
pi/4 = 1/2tan-1x + tan-1x
3/2tan-1x = pi/4
tan-1x = pi/6
x = tan(pi/6)
x = 1/√3
tan-1(1) - tan-1x = 1/2tan-1x
pi/4 = 1/2tan-1x + tan-1x
3/2tan-1x = pi/4
tan-1x = pi/6
x = tan(pi/6)
x = 1/√3