Niven's Theorem concerns the values taken by this function on certain rational inputs. This function is used to represent the imaginary part of a complex number when converting to polar coordinates and is denoted with the hyperbolic function e to the x minus e to the negative x divided by two. The Taylor series for this function is equal to zero when x equals zero and the inverse of this function is the (*) cosecant function. For 10 points, name this function which for an angle alpha of a triangle is equal to the ratio 
Niven's Theorem concerns the values taken by this function on certain rational inputs. This function is used to represent the imaginary part of a complex number when converting to polar coordinates and is denoted with the hyperbolic function e to the x minus e to the negative x divided by two. The Taylor series for this function is equal to zero when x equals zero and the inverse of this function is the (*) cosecant function. For 10 points, name this function which for an angle alpha of a triangle is equal to the ratio of opposite over hypotenuse.
Niven's Theorem concerns the values taken by this function on certain rational inputs.
{sine} function