Recent content by jjredfish

Got it! Brilliant. Thanks so much, Mark.

Thanks again for your help, Mark. I am coming at this from a very low level of mathematical ability. I can follow along, step-by-step, when I see it, but I don't know how to solve things with the quadratic formula and I don't know how that would get turned into (x,y) that I can graph.

He went from: x^2 + ((x^2 − 0.8x + 0.4^2) / 0.6^2) = 1. To: (1 + 0.6^2) x^2 − 0.8x − (0.6^2 − 0.4^2) = 0. combining the line equation with the ellipse equation, using the quadratic equation. And from that, I got: 1.36x^2 - .8x - .2 = 0

Hi Mark44, thanks for your reply. Unfortunately, my math is extremely rusty/non-existent. With someone else's help, I have gotten to y=x-.4, and 1.36x^2-.8x-.2=0 but I don't know how to turn those into (x,y) that I can graph.

If you are looking at the upper right quadrant of an ellipse centered at (0,0), with a=1 and b=.6, and there is a 45 degree line drawn from (1,.6), how would I find the (x,y) coordinate where the line crosses the ellipse? (I have been out of school for a long time, this is not homework).

Thanks for taking the time to explain all this MrAnchovy. I will try to understand it, and let you know if I have any questions.

I tried using "x=a cos t", and "y=b sin t" to get the coordinates for the center of the radius (where slope=1), but I am getting nonsensical answers, so I am obviously doing it wrong.

So I replace the x with the slope, which = 1, in my case?

To MrAnchovy: I really don't want to argue. I appreciate what you are saying, but I don't have the time, ability, or money to buy/use a commercial fishing net. I need one or two fish, and may never go fishing again. Thanks.

Thank you, chingel, I finally know how to use fractional exponents now! And thanks to you I know the formula for the length of the radius at slope=1. One last question, if you don't mind... is there any way to know where either end of that radius is located in relation to the center of the...

To: rcgldr and chingel, thank you so much! You guys rock! Your posts are very helpful. It really helps that you simplified it for me and put it in terms I can understand and relate to the things I know. So, for the fractional exponent "3/2", the denominator is actually the root... so "2" is...

Hi MrAnchovy, thanks for your reply. Actually, the formula for the ellipse is the only complicated math in the entire program (the program itself is not about math), and it is the only remaining component keeping me from finishing so I would really appreciate if you would at least give it a...

Hi MrAnchovy, It is for part of a software program I am working on. I am 48 years old, so it is not for homework, if that is your concern. Have I described the problem well enough, in a way that is understandable/makes mathematical sense? Thanks

Hi janhaa, thank you for your interest. Sorry, that was the best diagram I could find, but the blue point should be ignored. It is not part of the issue. The issue is: if the red line (not drawn to scale) is the length of a radius, with its end point being on the ellipse (at the point where...

To janhaa: Sorry, that is completely over my head, and not in the form that I need it in (for my non-math brain). To anyone who may be able to help: The best way I know to describe what I am seeking is from my description above: R=b^2/a, and R=a^2/b are well-know, common, and standard...