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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 465

27^n+2 - 6*3^3n+3/3^n9^n+2

That is it.

Thanks.

I know only one thing - that is that I know nothing

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

Okay, so far I have this,where is the mistake?

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 465

That's perfect no mistake!

I know only one thing - that is that I know nothing

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

How about doing some factoring there?

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 465

It says we should simplify it. But I don't know if it could be factorized. I tried doing it but the six has given me a tough time, it cannot be reduced to have 3 in order to have the same base as the others.

I know only one thing - that is that I know nothing

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

How about simplifying 27^{3n+3} to start?

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 465

Okay,

= 3^3(n+2) = 3^(3n+6). You changed the exponent, please look at the original one above.

*Last edited by EbenezerSon (2013-07-23 07:19:10)*

I know only one thing - that is that I know nothing

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

I was thinking of

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 465

At the back of the book the answer given was 21.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

That is incorrect. If post #102 is correct the answer I am getting is 7. Please look closely at post #102 and make sure I have the right problem as you see it in your text book.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 465

Yes, they are the ones in the book, the book could be wrong so please let proceed.

I have instances, I had my calculations correct while it had it wrong.

I will post a question I know I am correct while it has it wrong.

*Last edited by EbenezerSon (2013-07-23 07:59:38)*

I know only one thing - that is that I know nothing

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

Hi;

Answer is 7.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 465

But I don't seem to understand those methods

I know only one thing - that is that I know nothing

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

Hi;

They are based on the laws of exponents. As far as I can see that is a tedious problem. There maybe something simpler but I can not see it.

What step is a problem?

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 465

This problem is from indices. So I had thought all the bases would be equal so I can take them off and simplify the exponent.

So I multiplied the six and the three which is eighteen and cannot be reduced to three, so that all the bases would be equall(to be three).

I know only one thing - that is that I know nothing

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

You mean multiple 6 * 3^(3n+3) ?

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 465

Yes to be > 18^(3n+3). But I see the eighteen cannot further be reduced to three, in order to have the same base with the others.

I know only one thing - that is that I know nothing

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

That is incorrect. You can not say

6 * 3^(3n+3) = 18^(3n+3).

You can always test an idea by substituting some numbers for the variable. Try n = 1 and use a calculator.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 465

Because so far all the problems I solved have the same bases, which is easy for me to take them off and simplify the exponent.

So I thought I could apply that on this problem.

I know only one thing - that is that I know nothing

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

That is why I turned them all into the same bases, that way you can cancel and multiply when needed.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 465

Then I need to learn the laws of exponents, or do indices also teaches that? If not then please could you assist me learn it?

Thanks for your assistance, God bless!

I know only one thing - that is that I know nothing

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

Yes, we can over the laws of exponents. Try here first.

Please look at these pages, they will help a lot.

http://www.mathsisfun.com/exponent.html

http://www.mathsisfun.com/algebra/varia … tiply.html

http://www.mathsisfun.com/algebra/exponent-laws.html

Do not worry if you can not absorb it all. It will come in time. Ask questions about anything you do not understand.

I am going to take a little break to do some chores be back later. Please look over those pages in the meantime.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 465

A^n = A*A*A*.....A*

I think it should be impossible in that regard, because it has raised to the n. Meaning n is dividing the A, like n/A.

I know only one thing - that is that I know nothing

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,776

A^n means A * A * A ... n times.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 465

I have learnt that 5^0 = 1. Can you explain to me why it is equal to one?

I know only one thing - that is that I know nothing

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