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You are not logged in. #1 20060104 18:35:52
Rotation of ConicsI dont think im really understanding this topic. For the problem xy  1 = 0, how do you get the angle of the rotation out of that? #2 20060104 22:14:40
Re: Rotation of ConicsWhat angle of rotation? IPBLE: Increasing Performance By Lowering Expectations. #3 20060104 22:22:23
Re: Rotation of ConicsI can't understand, too: Last edited by krassi_holmz (20060104 22:22:49) IPBLE: Increasing Performance By Lowering Expectations. #4 20060105 01:48:53
Re: Rotation of ConicsYou have to give the full problem. I'm sure the question isn't just, "Find the angle of rotation in xy  1 = 0." "In the real world, this would be a problem. But in mathematics, we can just define a place where this problem doesn't exist. So we'll go ahead and do that now..." #5 20060105 02:02:26
Re: Rotation of ConicsCan be 180 deg. IPBLE: Increasing Performance By Lowering Expectations. #6 20060105 09:47:02
Re: Rotation of ConicsNo the whole problem wasnt that but thats the only part I was stuck on, I know the angle of rotation is 45°. Its just a bad example. The roatation of an ellipse shows it better. Last edited by im really bored (20060105 09:48:45) #7 20060105 11:23:25
Re: Rotation of ConicsOk I figured it out. Just had to plug the a b and c values into the Cot2θ = ( a  c ) / b. Solving for that im getting θ as 30°. Then I plug it into x = x'cos 30  y' sin 30 and y = x' sin 30 + y' cos 30. #8 20060105 15:57:32
Re: Rotation of ConicsWell I figured out that one, id show what I came up with but I dont have the slightest clue how to show a graph like that on the computer. #9 20060105 20:53:04
Re: Rotation of ConicsWell done. Only for graphics. IPBLE: Increasing Performance By Lowering Expectations. #10 20060105 20:54:36
Re: Rotation of ConicsHere's your ellipse(the first problem): Last edited by krassi_holmz (20060105 20:55:05) IPBLE: Increasing Performance By Lowering Expectations. #11 20060105 20:56:18
Re: Rotation of ConicsIs this works? (plot is streched a little, but the numbers are correct) IPBLE: Increasing Performance By Lowering Expectations. #12 20060106 12:02:09
Re: Rotation of ConicsYeah it looks just like what I got, and much more accurate. I never liked drawing elipses. For the second problem I finnaly figured out how to keep it clean, just use the half angle formulas for the cos and sin values. 