(a)

The area of the region is bounded by , , and .

Area of the region is the sum of areas of the set of inscribed rectangles.

In the first case, the rectangle repeat at an interval of .

In the second graph, the rectangle repeat at an interval of .

.

(b)

The area of the region could be more accurate when there are more number

of rectangle.

More the number of rectangle, more accurate will be the area.

(a) Area of the region using rectangle in it is .

Area of the region using  rectangle inscribed in it is .

(b) The area of the region could be more accurate when there are more number

of rectangle.