#include <stdio.h>
#include <stdlib.h>
#include <math.h>
int main(void)
{
double tg, A, B, S, x;
printf ("Enter х:\n");
scanf ("%lf", &x);
tg=tan(x);
if (tg<=0 || tg==1) printf ("Error\n");
else
{
A=sqrt(abs((log(tg))*(log(tg))-123));
B=exp(-3*x)+atan(x);
if (B==0) printf ("Error\n");
else
{
S=A/B;
printf ("%lf\n", S);
}
}
system("PAUSE");
return 0;
}