# Thread: Find a closed form expression for the nth right Riemann sum of this integral.

1. ## Find a closed form expression for the nth right Riemann sum of this integral.

Consider the following definite integral:

. . . . .$\displaystyle \int_6^{11}\, (-5x\, +\, 1)\, dx$

Find a closed-form expression for the nth right Riemann sum of this integral.

How do you figure these kind of questions out?

2. Originally Posted by DeezNuts
Consider the following definite integral:

. . . . .$\displaystyle \int_6^{11}\, (-5x\, +\, 1)\, dx$

Find a closed-form expression for the nth right Riemann sum of this integral.

How do you figure these kind of questions out?
You need to remember and then apply to your SPECIFIC problem the GENERAL definition of a right Riemann sum, namely

Expressed in function notation it is: $\displaystyle \sum_{j=1}^n \,\Bigg[\,\bigg\{f\left ( a\, +\, j\, \cdot\, \dfrac{b\, -\, a}{n} \right )\bigg\}\, \cdot\, \bigg\{ \dfrac{b\, -\, a}{n}\bigg\}\,\Bigg]$

In your specific problem, what is the value of a?

The value of b?

And what is f?

What will be the argument of f (the part inside the parentheses after the f) when j = n?

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•