# Calculating Moments

1. Jul 3, 2008

### City88

Hi there...
I'm not sure how to go about finding the following moments:

$$M_{x}= \int \int\$$ y dx dy
$$M_{y}= \int \int\$$ x dx dy

Where the region is bounded by the ellipse:
$$\frac{(x-2)^2}{16}} + \frac{(y-4)^2}{36}}$$ = 1

I tried this several ways. I drew the ellipse and found the bounds to be
-2 $$\leq y$$ $$\leq10$$
-2 $$\leq x$$ $$\leq 6$$

Then I tried integrating with those bounds, but I can't seem to get the right answers. Any help/hints would be greatly appreciated.

Last edited: Jul 3, 2008
2. Jul 3, 2008

### maze

Consider changing variables to center the ellipse around zero. eg:
u = x - 2
v = y - 4

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