The value range of X when TaNx = 0
x = 0,±∏,±2∏,±3∏,.
In (0,2 π), the value range of X which makes TaNx > 1 hold is
In (0,2 π), the value range of X which makes TaNx > 1 hold is
π/4
The value range of tanx-1 ≥ 0 is
∏/4+k∏≤x