I am getting errors in the polynomial equation x.I hav no idea whats wrong.This equation was provided.My code is as followed

Code:

#include<stdio.h>
#include<stdlib.h>
int main(void)
{
double x;
double polynomial=3x^3-5x^2+6; /*This is giving me problem*/
x=2.55;
printf("The value of polynomial is %lf\n",polynomial);
system("pause");
return(EXIT_SUCCESS);
}