Im getting the wrong roots when running the program. The maths the program is based on is in the attatched image.

Code:#include <stdio.h> #include <stdlib.h> #include <math.h> #define pi 3.14159265 int sign(float s); int main() { float a1, a2, a3, x1, x2, x3, s, q, th, s_sq, q_cub, a1_sq, a1_cub, s_abs; printf("The cubic equation has the form x^3 + a1x^2 + a2x + a3 = 0\n"); printf("Enter a1: "); scanf("%f", &a1); printf("\nEnter a2: "); scanf("%f", &a2); printf("\nEnter a3: "); scanf("%f", &a3); a1_cub = pow(a1, 3); a1_sq = pow(a1, 2); /* calculate q and s */ q = ( a1_sq - (3 * a2) ) / 9; s = ( (2 * a1_cub) - (9 * (a1*a2) ) + (27 * a3) ) / 54; /* get square / cube of s and q */ s_sq = pow(s, 2); q_cub = pow(q, 3); s_abs = fabs(s); /* ****** */ th = acos( (s/(sqrt(q_cub)) )); /* calculate theta */ if( (q_cub - s_sq) >= 0) /* cubic equation has 3 roots */ { x1 = ((-2)*(sqrt(q))*(th/3)) - (a1/3); x2 = ((-2)*(sqrt(q))*((th + (2*pi))/3)) - (a1/3); x3 = ((-2)*(sqrt(q))*((th + (4*pi))/3)) - (a1/3); printf("\nx1 = %f\nx2 = %f\nx3 = %f\n", x1, x2, x3); } else if( (s_sq - q_cub) > 0 ) /* cubic equation has 1 root */ { float part1 = sqrt(s_sq - q_cub) + s_abs; x1 = -(sign(s)) * ( (pow(part1, (1/3))) + (q/(pow(part1, (1/3)))) ) - (a3/3); printf("\nx1 = %f", x1); } else { printf("something crap happened\n"); } system("pause"); return 0; } int sign(float s) { if(s > 0) { return 1; } else if(s < 0) { return -1; } }