Computer Science Canada Math Question |
| Author: | zero-impact [ Sat Oct 24, 2009 8:26 pm ] |
| Post subject: | Math Question |
Yesterday there was an interesting bonus question on my gr12 advanced functions test that I was unable to solve. For which non-zero real number does,  give a positive integer?
From what i can tell, giving it a positive real will give 0 and giving a negative will always give a negative. Any thoughts? |
|
| Author: | DtY [ Sat Oct 24, 2009 9:21 pm ] |
| Post subject: | RE:Math Question |
You sure it wasn't a trick question? As far as I can tell, it can be simplified to 0 where x>0, or -2 where x<0 |
|
| Author: | bbi5291 [ Sat Oct 24, 2009 10:37 pm ] |
| Post subject: | Re: Math Question |
When I read this, I thought to myself: "OMG, compsci.ca has LaTeX support! Yaaay!" Then I read the code for your post. 
Anyway, I think your reasoning is sound... I see no way that this could ever be positive at all, let alone a positive integer. |
|
| Author: | zero-impact [ Sat Oct 24, 2009 11:48 pm ] |
| Post subject: | RE:Math Question |
Thank you, maybe I'm not crazy after all... O_O |
|
| Author: | A.J [ Sun Oct 25, 2009 9:32 am ] |
| Post subject: | RE:Math Question |
Well, plug in x = k and x = -k (where k is a positive real number). You'll notice that when x = k, the expression yields 0, and when x = -k, the expression yields -2... So you are right. |
|
| Author: | zero-impact [ Mon Oct 26, 2009 4:36 pm ] |
| Post subject: | RE:Math Question |
Well, I was right. But stupid me didn't write anything for the answer assuming there was actually some kind of tricksy answer... >.< |
|
| Author: | andrew. [ Mon Oct 26, 2009 5:05 pm ] |
| Post subject: | RE:Math Question |
You should always write an answer even if it's wrong unless you get marks deducted for wrong answers. |
|
| Author: | Brightguy [ Fri Nov 06, 2009 1:25 am ] |
| Post subject: | Re: Math Question |
bbi5291 @ Sat Oct 24, 2009 10:37 pm wrote: When I read this, I thought to myself: "OMG, compsci.ca has LaTeX support! Yaaay!"
I know how you feel, compsci.ca actually used to have LaTeX support. It was glorious. |
|
| Author: | andrew. [ Fri Nov 06, 2009 3:44 pm ] |
| Post subject: | RE:Math Question |
Why doesn't it now? LaTeX support would be great. |
|
| Author: | Brightguy [ Sun Nov 08, 2009 5:22 am ] |
| Post subject: | Re: Math Question |
Probably because there isn't enough mathematical discussion to warrant it. I've been making an effort for years to change that but the fact remains this place is overrun by programmers.  |
|