fonctions trigos

float cos(float a, int p)
{
    float u = 1.0;

    for(p=2*p-1; p>=1; p-=2)
        {
        u = 1 - a*a/ (p*p+p) * u
        }

    return u;
}

//cos(angle) = u

float sin(float a, int p)
{
    float u = 1.0;

    for(p=2*p; p>=2; p-=2)
        {
        u = 1 - a*a/ (p*p+p) * u
        }

    return u * a;
}

//sin(angle) = u