IA Type I -- Logarithm Bases

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I have my first portfolio due this week and I have no idea how to start!

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Hi,

I'm also currently doing the Logarithm Bases type 1 portfolio. The first question is quite simple, the last sequence pretty much gives away the pattern. For expressing the equation in the form p/q, try re-writing the sequences with the logarithms in the form x where log a B = x.

After you get there the last part is pretty much cake! (Actually this is really easy compared to some of the other portfolio tasks!)

The only question I have is if anyone knows how to justify their answers using technology WITHOUT using a calculator? I don't want to convert all the logs to base 10.

Gah, I'm so lazy. I guess I'll just do it that way, if no one has any other suggestions.

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you can justify your logs using tables, without the need to convert to base 10, like they used to do before calculators were widespread

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Convert it into base 10, you want those technology marks. I think I did some of them using the natural base to make it look fancier .

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I'm stressed.!!! don't know how to start my portfolio ;(

Can anyone help?????

The question I'm stuck in is

' Find the expression for the nth term of each sequence.

log(base2)8 , log(base4)8 , log(base8)8 etc

log(base3)81 , log(base9)81 , log (base 27)81 etc

log(base5)25 , log(base25)25 , log(base 125)25 etc

.

.

.

log(base m)m^k , lob(base m^2)m^k , log (base m^3) m^k etc.

Write your expressions in the form p/q.

.

.

.

what does it mean??????

and if possible, can anyone send me a copy of their work??? I don't know how to set out my work

Edited by HJ:)

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what does it mean??????

They want you to convert each term into a fraction ("in the form p/q"), find a pattern and give an expression in terms of n for the nth term.

Edited by Max

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I am having the same portfoilo atm, and it's quite clear that the fist sequence can be expressed as 3/x. the first number in the sequence is 3 , the second is 1,5 and the third is 1.

the first number in the sequence

3/1=3

the second

3/2=1,5

Det thrid term, which is log[8]8 , 3/3=1

hope you now see the pattern.

And if you calculate on the last sequence on the first part you'll find out this is true. though this is the easy part of the portfolio, at least that is my impression.

greetings from the Vikings in the far north;)

Edited by deissi
too much info :)

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They want you to convert each term into a fraction ("in the form p/q"), find a pattern and give an expression in terms of n for the nth term.

thank you soooooo much! I get the question now It helped me alot. I owe u one

Edited by HJ:)

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Well as you see on the last sequence

log[m^1]m^k , log[m^2]m^k , log[m^2]m^k , log [m^3]m^k

if you study the first number in the sequence you will see this

m^1x=m^k ergo k/1=x

second term in the sequence goes like this

log[m^2]m^k if you want to find which number this is

m^2x=m^k

x=k/2

and her comes the explination for why you can write it as k/n . If you look at the exponent in the base, and think of that as a number. you'll find ouy that is what decides the final number. are ypu following? this is getting quite messy, though i hope you understand some of it...

use of index laws^^ I hope you know them cause else this will be greek for you comrad. Just add me on MSN and I'll be glad to help you.

[email protected]

Edited by Alfabeta

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im having the same portfolio.

i got the first question, but i dont get the second one.

Now calculate the following, giving ur answers in the form of p/q

log(base4)64, log(base8)64,log(base32)64

log(base7)49, log(base 49)49, log(base 343)49

etc.

describe how to obtain the third answer in each row from the first 2 answers. Create two more examples that fit the pattern above.

Let log(basea)x=c and log(base b)x=d. Find the general statement that expresses log(base ab)x in terms of c and d.

can anyone give me some examples for it? thanks.

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im having the same portfolio.

i got the first question, but i dont get the second one.

Now calculate the following, giving ur answers in the form of p/q

log(base4)64, log(base8)64,log(base32)64

log(base7)49, log(base 49)49, log(base 343)49

etc.

describe how to obtain the third answer in each row from the first 2 answers. Create two more examples that fit the pattern above.

Let log(basea)x=c and log(base b)x=d. Find the general statement that expresses log(base ab)x in terms of c and d.

can anyone give me some examples for it? thanks.

No, we can't give you examples: we can't solve it for you. I've done this IA and I can tell you its very simple when you look at it, just take a while to look at the sequence. It's nothing more than a single easy fraction, just x/y.

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oh i got it. tahnks.

but then it says calculate the answer and gives it in the form of p/q

but like log(base4)64=3, it isnt a fraction. how do i get it in the form of p/q

do i put 3/1 or what?

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What do you mean by change it to base 10?

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i need help.....

i got all the math but how do you like format it and put it into words and what is the scope and limitation?!??!?!?

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im having trouble writing my introduction to this IA

would it be like "This assignment is looking for a general formula that will express logab x in terms of c and d."

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What do you mean by change it to base 10?

ok well lets say that its like Log28 so to convert it to the base 10 you do the following

Log8 divided by Log2 = Log10 8 i think lol

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im having trouble writing my introduction to this IA

would it be like "This assignment is looking for a general formula that will express logab x in terms of c and d."

are you talking about the second part of the question's intoduction or the introduction about the whole portfolio?? because the introduction only needs to be at the begining since the marker knows the questions already and all they need to find out is what you are going to be investigating in the beggining of ur paper.

after that u can just talk about the scope of ur portfolio, and what i mean by scope is what the portfolio is aiming to cover. thats what my teacher told me to do any ways

Edited by Jugedblue

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im stuck on the latter part of this IA. i found that logabx = (cd)/(c+d) but i cant figure out how to proof that, it kinda just made sense. and the last question is explain how you arrived at your general statement. so im really confused, any help would be much appreciated.

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ok im also having some trouble..

for the second part, where it says find an expression for the nth term in each sequence, did you guys get 3/n, 4/n, 2/n, and k/n?

when it says justify your answers using technology, do you just say what you graphing calculator said..or do you actually have to make a graph? how would you even make a graph?

when it says calculate the following in p/q form..for example for the first row would it just be 3,2,6/5? or would it be 3/1,2/1, 6/5?

In order to obtain the third answer in each row from the first tow answers..do you just multiply the first two bases of the first two logarithms to obtain the base of the third logarithm?

and how do you find the general statement?

help would greatly be appreciated..thanks!

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Maybe you could try applying the 'log_a b = 1/(log_b a)' rule.

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