Step 1 :

Definition :

If f is integrable on $\"\"$ , then

$\"\"$

Where $\"\"$ and $\"\"$ .

Step 2 :

The function is $\"\"$ and the interval is $\"\"$ .

Find the interval width with $\"\"$ and $\"\"$ .

$\"\"$

Subintervals are $\"\"$ and $\"\"$ .

Midpoints are $\"\"$ and $\"\"$ .

Find the Riemann sum :

$\"\"$

Step 3 :

Graph the function :

$\"\"$

The Riemann sum represents the sum of the areas of the two rectangles above the x - axis minus the sum of the areas of the three rectangles below the x - axis. \ \

Riemann sum is the net area of the rectangles with respect to the x - axis.

Solution :

$\"\"$