Jump to content

An annoying algebra probelm

Featured Replies

consider the set :

A = {(x,y) ε (N × N) | x <y , 2x^2 - 5xy + 2y^2 - x - y - 1 = 11}

 

The problem is to determine number of A's members. I have found x=2, y=6 as an answer. But I haven't been able to prove it's uniqueness and I'm not even sure about that. Because my solution is not complete, I don't bring it here. Can anyone help me on this?

You recognize that that is an ellipse in R^3 right? So there are only a finite number of things to check.

Ahhhhhhhhhhh, goddamit...

Now I got it!!

Thanks alot. This was gonna make me mad. I hadn't thought on it in this way!! :(

Archived

This topic is now archived and is closed to further replies.

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.