Redo problem 2 triangle.cc where you have to define and use the following functions: (a) isTriangle - takes 3 sides of a triangle and returns true if they form a triangle, false otherwise.

Redo problem 2 triangle.cc where you have to define
and use the following functions:
(a) isTriangle - takes 3 sides of a triangle and returns true if they form a triangle,
false otherwise.
(b) isIsosceles - takes 3 sides of a triangle and returns true if they form an isosceles
triangle, false otherwise.
(c) isEquilateral - takes 3 sides of a triangle and returns true if they form an
equilateral triangle, false otherwise.
(d) isRight - takes 3 sides of a triangle and returns true if they form a right triangle,
false otherwise.

this is the question and this is my work for problem 2

// This program prompts a user to enter the lengths of
// the 3 sides of a triangle, check if they form a triangle,
// and prints the triangle type: right, isosceles, equilateral,
// or scalene

#include <iostream>
#include <cmath>

using namespace std;

// Constant Declarations
const double E = .0001;

int main() {

  double side1, side2, side3;
  bool isTriangle, isRight, isEquilateral, isIsosceles;

  cout << "Enter the lengths of the 3 sides of a triangle -- ";
  cin >> side1 >> side2 >> side3;

  isTriangle = side1 + side2 > side3 &&
               side1 + side3 > side2 &&
               side2 + side3 > side1;

  if (isTriangle) {

    cout << "This is ";

    isEquilateral = fabs(side1 - side2) < E &&
                    fabs(side1 - side3) < E;

    isIsosceles = fabs(side1 - side2) < E ||
                  fabs(side1 - side3) < E ||
                  fabs(side2 - side3) < E;

    if (isEquilateral)
      cout << "an equilateral ";
    else if (isIsosceles)
      cout << "an isosceles ";
    else
      cout << "a scalene ";

    isRight = fabs(pow(side1, 2) - pow(side2, 2) - pow(side3, 2)) < E ||
              fabs(pow(side2, 2) - pow(side1, 2) - pow(side3, 2)) < E ||
              fabs(pow(side3, 2) - pow(side1, 2) - pow(side2, 2)) < E;

    if (isRight)
      cout << "and right ";

    cout << "triangle" << endl;

  } else
      cout << "This is not a triangle" << endl;

  return 0;

}