stupid, stupid, stupid
why do so many people think root 9 is plus minus three???
the root of nine is three. period. no buts about it.
how about minus three then, you say.
x^2=9
x= plus minus sqrt 9
x= plus minus 3.
arghhhhhhhhhh
why are people so dense!
ignore me. this is just a rant.
there. i feel much better.
Ok. For ranting about such a petty subject you’ve left yourself wide open. 
Capital letters are your friend. You’ve almost mastered punctuation (remember periods at the end of sentences, only one ? is neccesary, and questions end with a ?, not a !), now try capitalising the first word in any given sentence. It makes your posts far more legible.
It’s maths. No, I don’t care if you’re American. We came first, therefore we’re right. Comply or we shall assault you with posh accents.
Anyway, the square root of numbers is ill-define unless you’re considering a particular branch cut of the complex plane (or a riemann surface I think, but I’m not entirely sure what those are). The square root of a number is thus whatever you wan’t it to be.
+/- 3 is correct if you want to define the inverse of a non-injective function as the pre-image sets of points. It’s generally a pretty good way to do it IMO, but depends on context.
That’s the problem with ranting about maths. There’s always some pompous mathematician lurking around the corner who knows more about it. 
Umm, what the hell are you talking about?
I ain’t got much book-larnin’ when it comes to math. My checkbook is a mess.
I’m probably one of the above people about whom you’re ranting.
Ava
sotally tober - what’s the weather like on your planet?
kitarak wrote:
Damn right! This economizing on the letter “s” really struck me when i moved to the States. Try going into a clothing store - it’s even worse. There, you will find a sale on a nice wool PANT. It’s “pants,” you stupid fuckwits, unless perhaps you’re selling a garment with only one leg.
I have never seen “pant” in the singular. It might be a regional usage.
The only place I’ve seen “pant” in the singular is places like the Gap or the Limited, where they sell things like the “boot-leg pant” and the “chino pant.” So bitch if you want, but as far as I know, it’s only clothing stores that say that.
No, kitarak has it right (except for that silly “maths” thing ): -3[sup]2[/sup] and 3[sup]2[/sup] both equal 9. Of course, the only way you can get x[sup]2[/sup] = -9 is if you use your imagination.
I haven’t seen “pant” either (as a garment, that is, not a way of a dog to get rid of excess heat), except for the term “pant suit”.
True, but that doesn’t make it any more correct. And i’ve never seen this usage outside the US, although that doesn’t mean much - it could be common in the clothing industry internationally for all i know.
For example:
From this site:
From this site:
Sadly, the exponential function is not, in general, single-valued. It gets worse once you use complex arguments; then it has infinitely many values in some cases.
Complex analysis is fascinating, but it sucks.
sotally tober, you are, of course wrong. The definition of “square root of 9” is any number which when multiplied by itself equals nine and, so, (-3) fits the bill perfectly.
Actually, despite me being picky, in common usage he’s right. The square root of a positive real number is defined to be positive. My point was merely that there a lot of other senses you can mean ‘the square root’ in which he isn’t correct.
Ultrafilter: Wash that mouth out with soap. Complex analysis doesn’t suck at all, it’s marvelous! So there. 
Google brought these up in a matter of seconds:
http://www.sportsconnection.co.uk/products/34157340/
(The “Sanded Twill Pant”)
and
http://www.wheelbase.co.uk/trolleyed/13/21/187/
(The “Burton Tactic Vent Pant”)
So, it’s not just the U.S. where “pant” is used.
Burton Tactic Vent Pant would be a great SDMB uner name.
I confess to being one of those clueless, maths-inhibited people you’re probably ranting about. But I also have an excuse. I’m learning disabled!WHOOHOO!GO RETARDS!
IDBB
>> The square root of a positive real number is defined to be positive.
Where? I have never heard such thing. The definition I know of “square root of 9” is any number which when multiplied by itself equals nine and, so, (-3) fits the bill perfectly. And it could be a complex number as well. If you can find a turnip which when multiplied by itself yields 9 then that turnip is a square root of 9.
So, in essence, the OP is saying “I hate people who try to correct me when I’m obviously wrong.”
What…we have here is…failure…to communicate.
By convention, in order to make the square root a function, the square root of a nonnegative number is commonly defined to be a nonnegative number; so the square root of 9, for example, is indeed 3, and not -3.
When come back, bring pi