The density at each point of a 1 centimeter square (i.e., each side has length 1 centimeter) microchip is 4 + r2 grams per square centimeter, where r is the distance in centimeters from the point to the center of the chip. What is the mass of the chip?
We model the chip as the rectangle
Then the center is the point (0, 0) and the squared distance of a point (x, y) to the center is r2 = x2 + y2 . Thus the mass m can be computed as
