Question

"Find the moment about the x-axis of the homogenous region bounded by y = x , y = x + 4." What is it asking for????

Answer 1

Hmm I dunno :(

Answer 2

it sounds like they want they "moment of inertia" of a "plate" that has constant density \(\delta\).
\[ I= \int\int_A r^2 \delta \ dA \]
where r is the distance from the rotation axis. In this case, is the y value of each point in the region
\[ I= \delta \int\int_A y^2\ dA \]

Answer 3

But having said all that, the region bounded by y=x and y=x+4 goes on forever, so it's not clear....