## zhiyuan3yu5 2 years ago A plate occupies the region D shown in the diagram. ( a square with a square hole). the plate has surface density p(x,y)=9x^2 Find mass m of the plate.

1. zhiyuan3yu5

|dw:1353265298602:dw|

2. henpen

$9\int\limits_{y=-2}^{y=2}\int\limits_{x=-2}^{x=2}x^2dxdy-9\int\limits_{y=-1}^{y=1}\int\limits_{x=-1}^{x=1}x^2dxdy$

3. henpen

Tu comprende?

4. zhiyuan3yu5

oui

5. zhiyuan3yu5

merci.

6. henpen

Excellent