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0 votes
1 answer
77 views

how to write this region $D$ in relation to $r,\theta$ in this $\iint_Df(x,y)dxdy$ where $D=\{x^2+y^2 \le1,x+y\le 1\}$ and $D=\{x^2+y^2\le1,x+y\ge1\}$

I have attached two photos showing the integration bounds and I find it tricky how to express $r$ and $\theta$ in those two, if $x=r \cos{\theta}$ and $y=r\sin{\theta}$, so any help is very much ...
A Math Wonderer's user avatar
3 votes
1 answer
46 views

How do I find the bounds of this particular integral?

I want to convert this integral to Polar Coordinates to solve it: $\int_{0}^{2}\int_{0}^{\sqrt{y}}4xy^{2} \, dx \, dy$ What would be the bounds of $r$ and $\theta$ be? I know how to solve the integral ...
proof-of-correctness's user avatar
1 vote
1 answer
115 views

Evaluation of $~\iint_{D} {x^2-y^2 \over 1+x^4+y^4 } \mathrm{d}x \mathrm{d}y~$ where $~D~$is of bounded and closed and line symmetric with $~y=x$

$~D:=$domain where it is bounded and closed in $~ \mathbb R^2 ~$ and line symmetric with $~ y=x ~$ $$ I:=\underbrace{\iint_{D} {x^2-y^2 \over 1+x^4+y^4 } \mathrm{d}x \mathrm{d}y}_{\text{I want to ...
electrical apprentice's user avatar
1 vote
1 answer
1k views

Determining Bounds of Theta for Double Integration of a Polar Region

Given the region $$ R:(x, y | x^2 + y^2 \le 4x) $$ And given the function $f(x, y) = \frac{x}{\sqrt{x^2+y^2}}$, find the double integral of the polar region. So upon sketching the graph we get a ...
Stephen's user avatar
  • 11
0 votes
1 answer
28 views

Compute Triple integral for each "R" > 0

Compute for each $R >0$ the following: $$ \int\int\int (x^2 + y^2+z) dV\;\text{ over the region: }\;x^2 + y^2+z^2 ≤ 2Rz $$ I decided to use polar: Starting with $R=1$ rearranging the region I ...
ilovemathexchange's user avatar
0 votes
1 answer
60 views

calculating the area in polar coördinates

I have difficulties calculating the area and setting the right boundaries of the following polar coördinates: $$r=2(1+cos(\theta) ) $$ Thanks in advance
Wouter Lommerse's user avatar
1 vote
1 answer
341 views

polar coordinates for integral bounds with parallelogram as region

I'm having trouble with this problem: Evaluate the following double integral $$ \iint_D (x^2+y^2) \,\text d x\,\text dy $$ where $D$ is the region comprised of a parallelogram with the corners $(0,0)...
dekuShrub's user avatar
  • 399
2 votes
3 answers
139 views

Evaluating $\int_{-\infty}^\infty 1-e^{-\frac{1}{x^2}}{\rm d}x$

I am interested in the improper integral: $$I=\int_{-\infty}^\infty 1-e^{-\frac{1}{x^2}}{\rm d}x=2\int_{0}^\infty 1-e^{-\frac{1}{x^2}}{\rm d}x$$ which I am fairly sure converges. I broke the integral ...
aleden's user avatar
  • 4,027