Question

Could someone explain how to do this?
Approximate the volume above the xy-plane and beneath z=xy over the region 0<=x<=2, 0<=y<=4 by taking m=n=2 and using upper right points.

Answer 1

So the slope = 2 of the plane. You'll have to plot it using a 3D software, and then split it up into cuboids and other regular objects, and calculate the volume.

Answer 2

I'm sorry, I should have been more specific. My teacher has the answer as

Delta A=2 Z(1,2)= 2 Z(1,4)= 4
Z(2,2)= 4 Z(2,4)= 8
Estimate 2(2 + 4 + 4 + 8) =36

And 36 is the answer. I just don't understand the method. Thank you for any and all help.