Question

I’m working on an integration program using [right] rectangle sums. I am using the beginning bound as a=1, using ‘n’ as the # of rectangles, and ‘inc’ as the increment that increases z. Here is the code I have so far:

#include <iostream>
#include <cmath>

using std::cout;
using std::endl;
using std::cin;

int main(){

    int n;
    float b;
    float z;
    z=((b-1)/n);
    float inc;
    float new_sum;
    float sum;
    int decision;


    cout << "Would you like to calculate an area? " << endl;
    cout << "Enter 1 for yes, 0 for no: " << endl;
    cin >> decision;

    cout << "Please enter the number of rectangles you would like to use: " << endl;
    cin >> n;
    cout << "Please enter the upper bound of integration: " << endl;
    cin >> b;

    for (inc=0; inc < b; inc++){
        new_sum=z*(f(1+(inc*z)));
        sum=sum+new_sum;
    }

    cout << sum << endl;

return 0;

}

I have two questions:

1. How do I use the function f(x)=x^5 + 10 in this? I’m not sure how it should be inputted and formatted in the for loop.

2. How do I loop the first question sequence (Would you like to calculate an area?), using a for loop, to repeat until the user enters 1 for yes (I know how to do this with a while loop, but was wondering how it would be done with a for loop?)

Answer 1

How do I use the function f(x)=x^5 + 10 in this? I’m not sure how it should be inputted and formatted in the for loop.

float f( float x ) {
    return pow( x, 5 ) + 10; // maybe x * x * x * x * x + 10
}

add this lines before function main definition.

How do I loop the first question sequence (Would you like to calculate an area?), using a for loop, to repeat until the user enters 1 for yes (I know how to do this with a while loop, but was wondering how it would be done with a for loop?)

for (;;) {
    cout << "Would you like to calculate an area? " << endl;
    cout << "Enter 1 for yes, 0 for no: " << endl;
    cin >> decision;
    if ( decision != 1 ) // or if ( decision == 0 )
    {
        break;
    }

    cout << "Please enter the number of rectangles you would like to use: " << endl;
    cin >> n;
    cout << "Please enter the upper bound of integration: " << endl;
    cin >> b;

    for (inc=0; inc < b; inc++){
        new_sum=z*(f(1+(inc*z)));
        sum=sum+new_sum;
    }

    cout << sum << endl;
}