//See the attached figure for details.
//Drawing area (-2π, 2π)
Characteristics [Observation Area (0, π/2)]
(1)sinx and tanx are tangent at the origin.
(2)sinx (or tanx) is tangent to the straight line y=x and the origin.
(3)sinx and tanx have only one intersection.
(4)tanx & gt； X> Sinks
PS:
When sinx and tanx draw together, they must draw an auxiliary straight line y = X.