Partícula em queda livre

#include <stdio.h>
#include <math.h>

#define v0 20
#define theta0 60 //graus
#define y0 60
#define g 9.8

#define pi M_PI

int main (void)
{
double rad,tv1,tv2,y,x,t,v0x,v0y;

rad = 180*theta0/pi;

v0x=v0*cos(rad);
v0y=v0*sin(rad);

tv1=(v0y+sqrt(pow(v0y,2)+2*g*y0))/g;    //ver o maior dos valores para tv
tv2=(v0y-sqrt(pow(v0y,2)+2*g*y0))/g;



if (tv1==tv2)
{
for (t=0.0;t<=tv1;t+=0.1)
{
x=v0x*t;
y=y0+tan(rad)*x-(g*pow(x,2)/(2*pow(v0x,2)));
printf("%lf\t %lf\t %lf\n",t,x,y);
}
}

if (tv1>tv2)
{
for (t=0.0;t<tv1;t+=0.1)
{
x=v0x*t;
y=y0+tan(rad)*x-(g*pow(x,2)/(2*pow(v0x,2)));
printf("%lf\t %lf\t %lf\n",t,x,y);
}
}

if (tv2>tv1)
{
for (t=0.0;t<=tv2;t+=0.1)
{
x=v0x*t;
y=y0+tan(rad)*x-(g*pow(x,2)/(2*pow(v0x,2)));
printf("%lf\t %lf\t %lf\t %lf\t %lf\n",t,x,y);
}

}


return 0;
}