# Converting cartesian to polar coordinates in multiple integrals

1. May 25, 2012

### robertjford80

1. The problem statement, all variables and given/known data

Do you see how y gets converted to csc? I don't get that. I would y would be converted to sin in polar coordinates.

2. May 25, 2012

### Karamata

<deleted>

3. May 25, 2012

### robertjford80

thanks, I got it.

4. May 25, 2012

### robertjford80

I need to see what Karmata wrote again, if anyone knows I would appreciate it.

5. May 26, 2012

### robertjford80

still needing

6. May 26, 2012

### Karamata

Hi robertjford80!

I deleted my post because there was error in him (oh, bad English)

But, look at picture.

They said $\int_0^6 \int_0^y x \mbox{d}x\mbox{d}y$, that is yellow region (x from 0 (parallel y-axes) to x=y, y from 0 to 6). $r$ is moving from $r=0$ to y=6, so, $y= 6= r \sin \theta \Rightarrow r = \dfrac{6}{\sin \theta} = 6 \csc \theta$

#### Attached Files:

• ###### Untitled.png
File size:
1.7 KB
Views:
60
7. May 26, 2012

### robertjford80

ok, thanks, I got it. this so far has been one of the most difficult concepts in calculus to understand but I'm slowly getting it.