You code either find a C version of "math.h". I just wrote a smaller version with only basic trig functions declared:
Code:
double acos(double x);
double asin(double x);
double atan(double x);
double atan2(double y, double x);
double cos(double x);
double cosh(double x);
double sin(double x);
double sinh(double x);
double tan(double x);
double tanh(double x);