My Math Forum  

Go Back   My Math Forum > High School Math Forum > Algebra

Algebra Pre-Algebra and Basic Algebra Math Forum


Reply
 
LinkBack Thread Tools Display Modes
September 20th, 2007, 08:46 PM   #1
Newbie
 
Joined: Sep 2007

Posts: 2
Thanks: 0

Rotating an ellipse around an arbitrary point

Suppose I have the equation for an ellipse ... say for example, x^2/9 + y^2/16 = 1 ... and I want to rotate it (in the plane) around a point such as (2,2). How do I represent the equation for the rotated ellipse?

More generally, if I have any equation for an ellipse, possibly one that has even been translated up or down, and right or left, and I want to rotate it about any given point ... how do I represent the rotated ellipse?

Thanks! This one is driving me nuts!

John
johnrp is offline  
 
September 21st, 2007, 04:29 AM   #2
Global Moderator
 
CRGreathouse's Avatar
 
Joined: Nov 2006
From: UTC -5

Posts: 16,046
Thanks: 938

Math Focus: Number theory, computational mathematics, combinatorics, FOM, symbolic logic, TCS, algorithms
For one thing, you'll need to use parametric equations, since a nondegenerate rotated ellipse isn't a function.
CRGreathouse is offline  
September 21st, 2007, 06:06 AM   #3
Newbie
 
Joined: Sep 2007

Posts: 2
Thanks: 0

True. That's why I said I had an equation. For a standard ellipse, I would just use the standard form (x^2)/(a^2) + (y^2)/(b^2) = 1

Rotating this some arbitrary amount, like 37 degrees, would just look like a slanted ellipse. The equation for that however is still eluding me.

John
johnrp is offline  
Reply

  My Math Forum > High School Math Forum > Algebra

Tags
arbitrary, ellipse, point, rotating



Search tags for this page
Click on a term to search for related topics.
Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
Quadrature Weights for Arbitrary Sampling Grid chrispike Real Analysis 1 April 16th, 2014 11:39 PM
Exercises about subgroups of an arbitrary group. beesee Abstract Algebra 7 January 14th, 2013 10:22 AM
Probability of an Arbitrary Event under an Equally Likely As Mikev078 Advanced Statistics 2 December 8th, 2012 06:03 PM
Formula For Rotating a Point about another Point ManuLi Algebra 3 August 20th, 2009 02:25 AM
[Arbitrary-precision] Calculating mathematical constants CRGreathouse Applied Math 2 December 13th, 2006 08:12 PM





Copyright © 2019 My Math Forum. All rights reserved.