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#26 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 10:56:47
Thank you 
. Oh One last question. In this set: {(2,2),(1,3),(2,3),(3,3)} This isn't Reflexive because there's no (1,1)? Just double checking.
#27 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 10:38:38
True. I am ready for it, but there are bits that are too complex. I'm going to do my best for it.
#28 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 10:33:54
Yes I did. Just hope this doesn't pop up in the exam tomorrow.
#29 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 10:25:22
Ohhh I see. This looks quick a long process to solve this problem.
#30 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 10:16:07
OHH i get it.
#31 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 10:09:24
hmm..I'm not too certain on line 3. :'(
#32 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 09:50:23
Yea I get your example Its bringing back memories.
#33 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 09:40:21
Ohh i see.
#34 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 09:08:59
Ohh right. So what happens to 1? Doe that get subtractedm or replaced by (y-1) ??
#35 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 09:00:21
Ah ok. I was wondering does x count as 1 ?
#37 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 08:41:11
Yes I get that. /you multiply both sides.
#38 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 08:29:15
Okay. In 2/x, the x is just replaced by the (y-1) ??
#39 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 08:15:08
Ohh. You replaced the x that was above 2/ , and input (y-1) instead ?? That the right way of doing it??
#40 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 08:06:40
Ohhhhh! Silly me. From line 3 to 4, I got (y-1)/2, but your's the opposite round.
#41 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 07:58:58
Oh right! However, Why are you multiplying x, but not 2 ??
#42 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 07:51:54
I didn't get what happens after y-1 = 2/x. Can you explain how you got x(y-1)=2 ??
#43 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 07:40:30
Yes.. but it looks different 
#44 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 07:25:29
Hmmm you are right. I looked at the answer, an it says 'If f(x) = y, then 1+2/x = y and so x= 2/(y-1)'. I was wondering, where has the 2/(y-1) come from :S How did it get there??
#45 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-23 07:04:13
Sorry to ask you again But I have a small problem. It's a little off topic, but how would you answer this question...
The function f : A to B is given by f(x) = 1+ 2/x, where A denotes the set of
real numbers excluding 0 and B denotes the set of real numbers excluding 1.
Show that f is bijective and determine the inverse function.
I don't understand this question. Can anyone explain it to me?
#46 Re: Help Me ! » Puzzled with combinations and permutations. » 2012-01-23 01:02:07
Ohh. I guess most of it's common sense. I'll let you guys know if i get stuck on something in this topic.
#47 Help Me ! » Puzzled with combinations and permutations. » 2012-01-23 00:47:15
- BlitzBall
- Replies: 3
I understand the methods and differences. But, when I look at the questions, I can't determine whether order matters or not
#48 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-22 06:47:32
Ohhh I got it now. Going to do more practice on these! Thank you
#49 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-22 06:30:00
Yep I got that.
#50 Re: Help Me ! » Algebra help! Inverse and composition functions » 2012-01-22 06:18:15
Oh right i get that.