Double integral: \[\int \int_D e^{-2x-3y} dxdy\] \[D={(x,y): x\geq 0, y\geq 0, 2x+3y\leq 6}\]
I recommend you to first draw a sketch of the region or in this case maybe Dimension denoted as D.
They already give you the order of dimensions you're integrating with, \(dxdy\). So you want to see how \(x\) depends on \(y\).
|dw:1363274930063:dw|
Almost. Divide by 3 on both sides and \[y\leq2-\frac{2}{3}x\]
Exactly that is your region, so what you usually do in this step is fix a region and then see how x changes with respect to y. For the double integral to work out, the innermost integral has to be a function of the outer must integral after integration. Meaning like that: |dw:1363275368375:dw|
\(\large e^{-2x-3y} =e^{-2x}e^{-3y}\) integrating first w.r.t.x |dw:1363275993204:dw||dw:1363276120323:dw| sorry for bad drawing :P
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