Mathematical function, suitable for both symbolic and numerical manipulation.
The argument of Tan is assumed to be in radians. (Multiply by Degree to convert from degrees.)
Sin[z]/Cos[z] is automatically converted to Tan[z]. TrigFactorList[expr] does decomposition.
Tan is automatically evaluated when its argument is a simple rational multiple of ; for more complicated rational multiples, FunctionExpand can sometimes be used.
For certain special arguments, Tan automatically evaluates to exact values.
Tan can be evaluated to arbitrary numerical precision.