What is the Correct Order for Integrating in This Scenario?

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SUMMARY

The discussion centers on the correct order of integration for the double integral of the function \(x^2 + y^2\) over the region defined by the curves \(y = x^2\) and \(y = 2x\). The points of intersection are established at (0,0) and (2,4). The user initially sets up the integral as \(\int \int x^2 + y^2 \, dx \, dy\) with bounds \(b = y/2\) and \(a = y^{1/2}\), and later switches to \(dy \, dx\) with bounds \(b = x^2\) and \(a = 2x\). The user confirms that the change of order is correct despite initial confusion regarding the integration process.

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Pearce_09
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Hello,
Consider the integral:
[tex]\int_R x^2 + y^2 dA[/tex]

with the two graphs 2x-y = 0 and [tex]x^2[/tex] - y = 0

therefore y = [tex]x^2[/tex] and y = 2x are the two functions
and the point of intersection is at (0,0) and (2,4)

therefore
[tex]\int { \int x^2 + y^2 dx } dy[/tex]
(a - is top point of the integral and b - is the bottom)

therfor the domain for the first integral (dx) is b = y/2 and a = [tex]y^1^/^2[/tex]

and for the second integral (dy) is b= 0 and a = 4

but when i switch the order to """"" dy dx... i get a different #.

therefore my new a,b for the integrals are
for the first integral (dy) b = [tex]x^2[/tex] a = 2x
for the second integral (dx) b = 0 a = 2

is my change of order correct or did i do somthing wrong??
 
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never mind.. my change of order is correct.. i just messed up on my integration
thanks
 

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