### Home > APCALC > Chapter 2 > Lesson 2.2.2 > Problem 2-69

2-69.

Using sigma notation, write a Riemann sum to estimate the area under the function for

Since

Next, find the height of each rectangle. The height is determined by , where

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Finally, use sigma notation to represent the sum of all eight rectangles. Since these are left-endpoint rectangles, the index will start at , where

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Use your calculator to evaluate this sum.