Integral Approximation Equation Using Loop

Asked by Giulia Ferguson

Giulia Ferguson (view profile)

on 12 Sep 2019
Latest activity Answered by David Hill

David Hill (view profile)

on 12 Sep 2019
Write a Matlab function that approximates the integral of the equation [y =(√x) – x^2] from x= 0 to 1. Sub-divide the domain into N equal-width rectangles to approximate the integral. What is the approximate integral using N = 5, N = 50, and N = 200? Print the code.
Can anyone help me? I am so confused!

Answer by J Chen

J Chen (view profile)

on 12 Sep 2019

Generate a vector x=[0 1/N 2/N ... 1]. Calculate corresponding y for each element of x. Use the trapezoid rule to add all the y's. The sum is the aprroximation of the integral.

Answer by David Hill

David Hill (view profile)

on 12 Sep 2019

Sounds like standard definition of integrating where the width of the rectangles is eventually reduced to nothing.
n=5;
x=1/n:1/n:1;
area=sum((sqrt(x)-x.^2)*1/n);%problem does not say what to use as the height of the rectangle
change n to other values to get the other answers for create a loop.