#include <math.h>, syntax at the beginning of our code, means we automatically included these (pre-defined) functions in our program:
int abs (int x); IxI
long labs (long x);
double fabs (double x);
double sin (double x);
double cos (double x);
double tan (double x);
double asin (double x);
double acos (double x);
double atan (double x);
double sinh (double x);
double cosh (double x);
double tanh (double x);
double exp (double x); ex
double log (double x); ln x
double log10 (double x); log x
double pow (double x,double y); xy
double sqrt(double x); sqare root of x
double fmod(double x, double y); x mod y
double ceil (double x);
double floor(double x);
Technorati Tags: math.h, Library, #include, abs, long, double, mod
The only thing I'm missing here is the unit-system that is used for angular calculations (sin, cos, tan and its variants). I mean in the sense of radians, degrees, etc.
And as for the log(), you might want to put the base value thats used near it (base=e=2.718281828).
PS, another trick I like to apply myself when I need to calculate the root of another power than 2 is: pow(number, 1/power)