Mahuta ♥ Posted January 2, 2009 Report Share Posted January 2, 2009 What does it mean when it asks for the limitations/scope af a, b, and x?I've done that one...and i got 18:D:Dok...simply...they want you to briefly state concluding from your verifications..for what values of a, b and x does the equation work...and for what values doesnt it..thats all you have to say...it doesnt need to be long...as long as you go "crazy" on the verification part:D...goodluck! Reply Link to post Share on other sites More sharing options...
conbo1990 Posted January 2, 2009 Report Share Posted January 2, 2009 hello, I have Logarithm Bases SL type I, but I don't really understand what do they means by [Find an expression for the nth term of each sequence. Write your expressions in the form p/q...] would anyone explains what it means? Thank you sooo much. Reply Link to post Share on other sites More sharing options...
Chilean Hobbit Posted January 2, 2009 Report Share Posted January 2, 2009 Thanks everyone. I was stuck but I think I got it now. =] Reply Link to post Share on other sites More sharing options...
deissi Posted January 3, 2009 Report Share Posted January 3, 2009 Please, don't post solutions to the IA on the forum. All such posts will be deleted. Reply Link to post Share on other sites More sharing options...
Mahuta ♥ Posted January 3, 2009 Report Share Posted January 3, 2009 (edited) hello, I have Logarithm Bases SL type I, but I don't really understand what do they means by [Find an expression for the nth term of each sequence. Write your expressions in the form p/q...] would anyone explains what it means? Thank you sooo much.yes sure I finished this exactly a month ago:You have several sequences. For each one, im assuming you already found the next two terms. From the seven terms now, you should be able to notice a pattern, this is the first sequence:N=1 : log(2)8N=2 : log(4)8N=3 : log(8)8N=4 : log(16)8...etcNow, the expression they want you to find for the nth term is basically the relationship between 'N' and and the base (as it is the one changing), in another words, what is it that we do to 'N' to get the base?When you find that expression, tell me. I'll explain to you then the second part. It will probably make sense to you before I even explain it,lol. hope this first part is helpful enough. Edited January 3, 2009 by mahuta Reply Link to post Share on other sites More sharing options...
superkdude Posted January 3, 2009 Report Share Posted January 3, 2009 (edited) Maybe you could try applying the 'log_a b = 1/(log_b a)' rule. in Log_a b=x, is there a proper term for b? I mean like a is the base, x would be the exponent or the answer, and then I looked up b and I found that it was called the argument, but I didn't know If that was right or not. can anyone confirm that for me? and on average, how long is this IA supposed to be? I'm getting at at least 10 pages to get all the information necessary and I don't know what "extra information" I can add in. Edited January 3, 2009 by superkdude Reply Link to post Share on other sites More sharing options...
deissi Posted January 3, 2009 Report Share Posted January 3, 2009 superkdude: I had the same problem as you did, there really exists no term for the b, at least according to my math teacher. I remember asking about the argument thing myself and she said most people won't know what you mean, so you don't want to take that risk. As for the length, anything between 6-16 pages is suitable, I should say. It really depends on the way you present it . Reply Link to post Share on other sites More sharing options...
conbo1990 Posted January 4, 2009 Report Share Posted January 4, 2009 (edited) yes sure I finished this exactly a month ago:You have several sequences. For each one, im assuming you already found the next two terms. From the seven terms now, you should be able to notice a pattern, this is the first sequence:N=1 : log(2)8N=2 : log(4)8N=3 : log(8)8N=4 : log(16)8...etcNow, the expression they want you to find for the nth term is basically the relationship between 'N' and and the base (as it is the one changing), in another words, what is it that we do to 'N' to get the base?When you find that expression, tell me. I'll explain to you then the second part. It will probably make sense to you before I even explain it,lol. hope this first part is helpful enough. Hello Mahuta ,thank you so much for replying my question. I am so happy that you care. I already finish the 1st part but I don't really know if I did it right. For the expression p/q, I found it likes this : 3/q ; therefore, q is an N numbers that 3 divides to find the result of log[base2]3, log[base4]8, log[base8]8, etc.So it is likes this:log[2]8=3 => 3/1=3 log[4]8=1.5 => 3/2=1.5log[8]8=1 => 3/3=1and so on 3/4, 3/5, 3/6, 3/7 for log[16]8, log[32]8, log[64]8, log[128]8. the last 2 are what I found.the base is double therefore, my expression is log[2n]8I hope what i did is right... please give me some suggestion...Thank you very much... Edited January 4, 2009 by conbo1990 Reply Link to post Share on other sites More sharing options...
Mahuta ♥ Posted January 4, 2009 Report Share Posted January 4, 2009 hey,look at this part again:N=1 : log(2)8N=2 : log(4)8N=3 : log(8)8N=4 : log(16)8The relationship between N and the base isnt really '2n'. If you look at what i just put, take N=4 for example, you wouldnt get 16 if you multiplied it by 2, would you? It's more N^2:1^2=22^2=43^2=84^2=16therefore, you could make a small change in your expression.The way you obtained the expression in the form of p/q is correct. But you're missing one more step. You need make that into a general expression:You said that:N=1 log[2]8=3 => 3/1=3 N=2 log[4]8=1.5 => 3/2=1.5N=3 log[8]8=1 => 3/3=1What do you notice about the 'N' and the denominator of that fraction you found?Thats where your general expression in the form of p/q comes from. Oh...and no problem. Reply Link to post Share on other sites More sharing options...
conbo1990 Posted January 4, 2009 Report Share Posted January 4, 2009 hey,look at this part again:N=1 : log(2)8N=2 : log(4)8N=3 : log(8)8N=4 : log(16)8The relationship between N and the base isnt really '2n'. If you look at what i just put, take N=4 for example, you wouldnt get 16 if you multiplied it by 2, would you? It's more N^2:1^2=22^2=43^2=84^2=16therefore, you could make a small change in your expression.The way you obtained the expression in the form of p/q is correct. But you're missing one more step. You need make that into a general expression:You said that:N=1 log[2]8=3 => 3/1=3 N=2 log[4]8=1.5 => 3/2=1.5N=3 log[8]8=1 => 3/3=1What do you notice about the 'N' and the denominator of that fraction you found?Thats where your general expression in the form of p/q comes from. Oh...and no problem. Thank you! i know what i did wrong now. However, i am not quiet sure about the expression of p/q. well, I notice that 'n' has to be Natural number 1,2,3,4...etc. And as the 'n' number increases, the value of log[n]8 or the fraction decreases. This is the equation that i can come up with : log[base2^n]8Also, for p/q is 3/n where n is natural numbers.I spent almost like a whole day the for second part. One thing i am confused about that when it said, "logPost by: Aboox=c and logx=d. Find the general statement that expresses log[ab]x, in terms of c and d." I know how to do it, but i wonder if i need to apply that expression into the sequences they gave me such as log[4]64, log[8]64, log[32]64 ; log[7]49, log[49]49, log[343]49, and etc...or just provide a number for a,b,x and test if my general statement is correct? I have one more day left to do this project. crying...i am so scared that i will not finish it. =[ Reply Link to post Share on other sites More sharing options...
deissi Posted January 4, 2009 Report Share Posted January 4, 2009 Once again, I'd like to remind people NOT to give the general expression. Unfortunately it's something we all have to find for ourselves. We are already on the borderline of too much information here. Reply Link to post Share on other sites More sharing options...
Mahuta ♥ Posted January 4, 2009 Report Share Posted January 4, 2009 Thank you! i know what i did wrong now. However, i am not quiet sure about the expression of p/q. well, I notice that 'n' has to be Natural number 1,2,3,4...etc. And as the 'n' number increases, the value of log[n]8 or the fraction decreases. This is the equation that i can come up with : log[base2^n]8Also, for p/q is 3/n where n is natural numbers.I spent almost like a whole day the for second part. One thing i am confused about that when it said, "logPost by: Aboox=c and logx=d. Find the general statement that expresses log[ab]x, in terms of c and d." I know how to do it, but i wonder if i need to apply that expression into the sequences they gave me such as log[4]64, log[8]64, log[32]64 ; log[7]49, log[49]49, log[343]49, and etc...or just provide a number for a,b,x and test if my general statement is correct? I have one more day left to do this project. crying...i am so scared that i will not finish it. =[Ummm, you actualyl shouldnt have left it to the last moment, i mean there's a reason why we're given 2 weeks:S.But anyhow, as for the general expression, all i can tell you is that you're on the right track.This is something all teachers told us: When you get to the justification/testing, just go crazy on it,lol.I can tell you that the whole project is related, everything you found in the first part is there to help you with the second part. oh...and deissi, I'm not giving any answers, im just guiding like the way my teacher did, I promise. Reply Link to post Share on other sites More sharing options...
conbo1990 Posted January 4, 2009 Report Share Posted January 4, 2009 Ummm, you actualyl shouldnt have left it to the last moment, i mean there's a reason why we're given 2 weeks:S.But anyhow, as for the general expression, all i can tell you is that you're on the right track.This is something all teachers told us: When you get to the justification/testing, just go crazy on it,lol.I can tell you that the whole project is related, everything you found in the first part is there to help you with the second part. oh...and deissi, I'm not giving any answers, im just guiding like the way my teacher did, I promise.My teacher didn't say anything about the project. He just passed it out and didn't say much about it. All he said is that this is an individual effort. Therefore, for the 1st week, i tried to figure it out by my own. However, i just don't really understand some terms, therefore, last couple days, i get on internet and study logarithm. Then i found this website therefore, i ask some questions. Well, i finished mostly the second part, i just need to test it. lol. a lot of work, but yeah i will finish it. Thank you so much for helping me. Reply Link to post Share on other sites More sharing options...
superkdude Posted January 4, 2009 Report Share Posted January 4, 2009 (edited) Thank you :-) and my last question on this IA is what are the limitations of a, x, and b? I found that X must be positive in log_a X and log_b x because you can't take the log of a negative number, but what limits a and b? I thought since a was the base, it wasn't limited to anything, but I'm not sure. Edited January 5, 2009 by superkdude Reply Link to post Share on other sites More sharing options...
o1.Danniiee Posted January 5, 2009 Report Share Posted January 5, 2009 I believe that to be only partially true, there is one condition where log of a negative number can be taken. However, you must convert it to a different form if you understand. As far as I know, that's the only limitation. Good Luck. Reply Link to post Share on other sites More sharing options...
Mahuta ♥ Posted January 5, 2009 Report Share Posted January 5, 2009 You're welcome:D, goodluck! Reply Link to post Share on other sites More sharing options...
deissi Posted January 5, 2009 Report Share Posted January 5, 2009 It can't be negative, not in SL Math. Reply Link to post Share on other sites More sharing options...
Mahuta ♥ Posted January 5, 2009 Report Share Posted January 5, 2009 (edited) negative values in logarithms are mathematically correct. Here's an example:log(-2)-8=3: we have a negative base and a negative number here, yet the equation is mathematically correct.In my project, my teacher was like make sure you mention ALL limitations and why to garuntee the marks, and he was right, i got 18 on that one.So yeah, it wouldnt do harm to just mention it. Edited January 5, 2009 by mahuta Reply Link to post Share on other sites More sharing options...
deissi Posted January 5, 2009 Report Share Posted January 5, 2009 The problem is that you can't simply mention, you have to also state why it is so. But here, I see what you mean. However, don't forget that it is the same teacher telling you what to do and evaluating you. They might not always be right, always take the stuff your teacher says with a pinch of salt. Reply Link to post Share on other sites More sharing options...
Mahuta ♥ Posted January 5, 2009 Report Share Posted January 5, 2009 Exactly, that's why I said 'and why'. It's true, but those people he guided the same way last years, had their project moderated by IBO, and got the same mark given by the teacher. In a way it makes sense though, because you're like mentioning all possible limitations and simply explain why, that would look good on your project and you would score higher on the justification criterion.But anyhow, this was just a suggestion:).Thanks deissi though. Reply Link to post Share on other sites More sharing options...
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