All the trig functions have inverses: inverse of sin is arcsine or sin-1; cos is arccos or cos^-1; tan is arctan or tan^-1; and so on. The inverse property is sin(arcsin(x))=arcsin(sin(x)). This property is shared by all the inverses: if f is the trig function and f^-1 is the inverse, then f(f^-1(x))=f^-1(f(x)). The limits for the angles are between -90° and +90°, and limits for the inverses are between -1 and +1. However, some of the functions are not defined at the extremes: at 0, 90°, -90°, for example, tan 90° cannot be defined (infinity). There are also inverses to the reciprocal functions: cosecant or cosecant or csc (1/sin), secant or sec (1/cos), cotangent or cot (1/tan). These give rise to other properties: sin^-1(1/x)=cosec-1(x), cos^-1(1/x)=sec^-1(x), etc. It's useful to draw a right-angled triangle to help picture the relationship between sides and angles in terms of the trig functions, their reciprocals, their inverses, and the inverses of the reciprocals.