A community for students.
Here's the question you clicked on:
 0 viewing
anonymous
 3 years ago
prove that the directrix of an ellipse is \[x=\frac{a^2}{c}\]
anonymous
 3 years ago
prove that the directrix of an ellipse is \[x=\frac{a^2}{c}\]

This Question is Closed

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0this ellipse is the general ellipse with \[\frac{ x^2 }{ a^2}+\frac{ y^2 }{ b^2 }=1,a>b\]

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0i have the proof but i dont understand the ratio set up here can i post the link

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0\[r=\frac{ ac }{ da }=\frac{ a }{ d }\]

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0\[a^2=b^2+c^2 i dont get this ratio .why it holds

experimentX
 3 years ago
Best ResponseYou've already chosen the best response.1??dw:1364055606757:dwdw:1364055629069:dw

experimentX
 3 years ago
Best ResponseYou've already chosen the best response.1i haven't done conics for quite while, but this shouldn't be difficult.dw:1364055735803:dw

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0i mean http://mathworld.wolfram.com/images/equations/Ellipse/NumberedEquation12.gif

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0its defined in the 1st link

experimentX
 3 years ago
Best ResponseYou've already chosen the best response.1can't find it ... equation no?

experimentX
 3 years ago
Best ResponseYou've already chosen the best response.1what is this 'c' again?

experimentX
 3 years ago
Best ResponseYou've already chosen the best response.1this 'c' looks like foci.

experimentX
 3 years ago
Best ResponseYou've already chosen the best response.1this is pretty ovbioius ... this ratio must be constant
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.