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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,921

Hi;

Okay, take all the time you need.

**In mathematics, you don't understand things. You just get used to them.**

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 475

bobbym wrote:

I was interrupted by some errand, boring one indeed.

Bobbym, it seems you mistakenly made a negative sign a positive sign.

The original is the same as the one Anomnystify solved please check the sign at #244. I mean;

3(x-1)/x-9,

Which you made it

3(x+1)/x^2-9.

*Last edited by EbenezerSon (2013-08-08 20:32:27)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,921

Hi;

I wrote, that there is a mistake in line 2 of post #244

EbenezerSon wrote:

anonimnystefy wrote:Hi EbenezerSon

With a careful look at signs I think should be,

x-3x-3-3/x^2-9 =-2x-6/x^2-3^2 =

-2(x+3)/(x-3)(x+3)

= -2/x-3Please am I right there.

Thanks.

**In mathematics, you don't understand things. You just get used to them.**

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 475

Please, I mean the problem itself.

You made a negative sign a positive sign.

Here ;

3(x-1). Which you made it 3(x+1).

You check it from one of your post.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,921

The first line is 3(x+1)

The second line changes that to 3x - 3, that is a mistake.

**In mathematics, you don't understand things. You just get used to them.**

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 475

Please look at #252.

That is the original question.

The first line is -3(x-1).

And changes the second to be,

-3x+3

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,921

You are not understanding what I am saying. Post #244 is wrong at the second line.

Please post the original problem from the book.

**In mathematics, you don't understand things. You just get used to them.**

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 475

1/1+3 - 3(x-1)/x^2-9.

That is it.

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

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,921

And what did you get for an answer?

**In mathematics, you don't understand things. You just get used to them.**

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 475

I am not at home now, I will post the original when I get there.

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: 92,921

Okay, see you then.

**In mathematics, you don't understand things. You just get used to them.**

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 475

Hi, Bobbym.

This is the one from the book;

1/x-3 - 3(x-1)/x^2-9

I had -2/x+3 as answer.

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

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,921

Hi;

That is correct!

**In mathematics, you don't understand things. You just get used to them.**

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 475

bobbym wrote:

Hi;

How did you get,

9^n+2 * 3^n+2 out of 27^n+2?

I have edited it.

*Last edited by EbenezerSon (2013-08-11 04:17:33)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,921

Hi;

I did not get that. Where does 23^n come from?

**In mathematics, you don't understand things. You just get used to them.**

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 475

Please, I double check it I have edited.

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: 92,921

27^a = 9^a * 3^a

**In mathematics, you don't understand things. You just get used to them.**

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 475

It's 27^n+2, and not 27^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: 92,921

You can say a = (n+2), same principle.

27^(n+2) = 9^(n+2) * 3^(n+2)

**In mathematics, you don't understand things. You just get used to them.**

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 475

I suppose the base must always be the same in each case. So I percieved it to be,

27^n+2=27^n*27^2=3^3n * 3^3+2.

I had thought should be so.

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

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,921

I am sorry, I can not follow that. Please bracket it off.

**In mathematics, you don't understand things. You just get used to them.**

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 475

In fact I have not seen an indicial problem being split to get different numbers as the base. like what is in #269.

.Thiş problem is from indices.

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

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,921

You should learn to latex or to use parentheses better.

That modern notation they are using in that book is not good.

**In mathematics, you don't understand things. You just get used to them.**

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**EbenezerSon****Member**- Registered: 2013-07-04
- Posts: 475

27^n+2=27^n * 27^2

Thıs is how I mean, I will learn parenthesis in it proper way as you say.

For instance, 6^n+3=6^n * 6^3.

Because, for instance, 3^2 * 3^2=3^(2+2).

What do you say.

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

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,921

All of that is correct but I have to interpret every bit of it.

When you write 27^n+3 in mathematics that means

It is properly written 27^(n+3) this means

Notice they are both very different.

**In mathematics, you don't understand things. You just get used to them.**

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