Find TaNx when sin (x / 2) - cos (x / 2) = 0

Find TaNx when sin (x / 2) - cos (x / 2) = 0

[sin(x/2)-cos(x/2)]^2=0
1-2sin(x/2)cos(x/2)=0
1-sinx=0
sinx=1 cosx=0
TaNx = SiNx / cosx = 1 / 0 is nonexistent