Quantcast surd inequality - XP Math - Forums
XP Math Home Sign Up FREE! | Sign In | Classroom Setup | Common Core Alignment PDF Version

Go Back   XP Math - Forums > Mathematics > Homework Help

Reply
 
Thread Tools Display Modes
Old 12-31-2007   #1
agripa
Guest
 
Posts: n/a
Default surd inequality

please help with it:

square root(x+2-x^2)<square root(x^2-3x+2)+x

Last edited by agripa; 01-01-2008 at 10:23 AM..
  Reply With Quote
Old 01-01-2008   #2
MyriamK
Guest
 
Posts: n/a
Default be careful

Square roots provide plenty of opportunities to make mistakes. So do inequalities.
There may be a much easier way that I don't see, but I would square.
If 0<a<b, then a^2<b^2
Since x+2+x^2 = (x+1/2)^2 + 7/4 > 0 , you can square to get
-x^2+4x < 2xsqrt(x^2-3x+2)
After that you have to consider cases (x<0, x>0, x=4, x>4, x<4, etc) and square again.

Happy New Year!
  Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 03:51 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2017, vBulletin Solutions Inc.
XP Math