The width of each rectangle is . The heights of the rectangles are found by evaluating y = 4 − x^2 at the
appropriate points.
Multiply each height by the width of , and add up the areas.
PROBLEM 5. Find the area under the curve y = 4 − x^2 from x = −1 to x = 1.
Answer: Now we can use the definite integral by evaluating.
(4 − x^2 ) dxThis can be rewritten as