Recent content by dluu

So I checked my work on Wolfram and I think this is correct. But when I try to plug in values, they don't work. I'm not sure what I'm doing wrong. Here is my work

I tried to do this and checked my math with Wolfram Alpha. I'm confused on one of the steps *for some reason I input x-1 but it kept putting 1-x* My question is how does this work? sin(2p) ----> s√(1-s^2 )

Thanks, I see how this works. One more question. Are my trig identities correct where: u = sin(theta-phi) du = cos(theta-phi)

Is this correct? Not sure where to go after this. *ignore 2nd to last line*

Okay I understand now. This is the general equation I should be using throughout excel. After working this out, I came to this equation. How do I integrate this?

Okay I'll try that way. So the picture of my previous post, would I use the -sqrt since its the lower curve?

On wikipedia it says: "the solution with a minus sign in front of the square root giving the same curve" http://en.wikipedia.org/wiki/Polar_coordinate_system If they're the same curve then I wouldn't need to use ##r_{outer}^2-r_{inner}^2## would I? What if my limits of integration was...

Yes they're the same.

Sorry I'll upload a better picture with a description Yes the r's are the same. I changed phi to gamma. Not sure why I did.

I asked a math professor at my university about this and we tried to do this converting a circle from cartesian to polar coordinates. The equation of the circle would result in a +- equation in front of the square root through quadratic formula. He used the equation: and told me to use the...

Homework Statement Hi, I'm trying to find the area of a circle in polar coordinates.I'm doing it this way because I have to put this into an excel sheet to have a matrix of areas of multiple circles. Here is an example of the problem. a= radius of small circle (gamma, r0) = polar coordinate...

sorry, wrong forum. delete thread

Hi, I'm not sure how to integrate this equation where a, r0 and γ are constants.

I think I went the wrong way with this problem. Here is a better picture: I am trying to find find a general equation to plug into Excel. Depending on location of the circle, radius, and limits of integration, will give a value of the area. I'm not sure using the polar equation of a circle...

Hi, I'm trying to find the area of a segment of a circle that is not at the origin. It will look similar to this picture below but I need to find the area enclosed by a circle. Using the polar equation of a circle provided by wikipedia: and integrating to find the area of a...