Code review in c

[DavidLacsao]

Guys, I need feedback on my code. I just need to know if this is a good way to do this at a beginner level and if the stated problem relates to my code.
The Problem:

Here is the code:

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

int factorialSolver(int num);
int powerSolver(int base, int p);

//
double discriminant(int a, int b, int c);
double oneRoot(int a, int b, int c);
double root1(int a, int b, int c);
double root2(int a, int b, int c);


int main() {

    char choice;

	printf("\n");

    do{
        printf("\n");
        printf("\nCHOOSE AN APP");
        printf("\na. Power Solver, b. factorial Solver, c. Quadratic Solver, q. Quit");
        printf("\nChoice: ");
        fflush(stdin);
        scanf("%c", &choice);

        if(choice == 'a' || choice == 'A') {
            int base, power;

            printf("Enter base: ");
            scanf("%d", &base);
            printf("Enter power: ");
            scanf("%d", &power);

            printf("%d raise to the power of %d is: %d", base, power, powerSolver(base, power));
        } else if(choice == 'b' || choice == 'B') {
            int num;

            printf("Enter a number: ");
            scanf("%d", &num);
             if(num > 0) {
                printf("The factorial of %d is: %d", num, factorialSolver(num));
            } else {
                printf("Invalid Input");
            }
        } else if(choice == 'c' || choice == 'C') {
            int a,b,c;

            printf("Enter a: ");
            scanf("%d", &a);
            printf("Enter b: ");
            scanf("%d", &b);
            printf("Enter c: ");
            scanf("%d", &c);

            if(a==0 && b==0) {
               printf("There is no solution");
            } else if (discriminant(a,b,c) < 0) {
               printf("There are no real roots");
            } else if(a==0) {
               printf("Root: %.2lf",oneRoot(a, b, c));
            } else {
               printf("Root1: %.2lf", root1(a,b,c));
               printf("\nRoot2: %.2lf", root2(a,b,c));
           }
        }
    } while(choice != 'q');
    printf("YOU EXITED");

	return 0;
}
//Power Solver

int powerSolver(int base, int p) {
	int result;
	result = pow(base, p);
	return result;
}
//Factorial Solver

int factorialSolver(int num) {
     int result=1;

	 for(int i=1; i <= num; i++) {
		 result *= i;
	 }
	 return result;
}

//Quadratic Solver
double discriminant(int a, int b, int c) {
   double answer;

   answer = b * b - 4 * a * c;
   return answer;
}

double oneRoot(int a, int b, int c) {
   double answer;

   answer = (-b / (double)c);
   return answer;
}

double root1(int a, int b, int c) {
  double result;
  result = (-b + sqrt(b * b - 4 * a * c)) / (2 * a);

  return result;
}

double root2(int a, int b, int c) {
  double result;
  result = (-b - sqrt(b * b - 4 * a * c)) / (2 * a);

  return result;
}

Sample output:

I think I am wrong in the quadratic part because I can’t seem to know how to implement the solution using only the quadraticSolver() function. So I just decomposed it into 4 functions.