More with left-hand and right-hand sums

Let's suppose we want to calculate the definite integral of x^2 from x=2 to 2=5.

First, let's call the upper limit b and the lower limit a. Let's also define the function

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Now, let's choose a value for n, the number of intervals. n will determine the width of the time (or x) interval.

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Maple also knows how to do integrate.

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Maple evalutes the integral using the Fundamental Theorem if it can. If it can't Maple can also determine the value of the integral numerically, by using left- and right-hand sums, or a variant thereof.

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