Need a check.{resolved}

I keep comming up with the same answer for this problem. :confused: 4/x² + 4x - (2 / x² - 4x) --> 2x -24 / (x+4)(x-4). My book has 2x -24 / x(x+4)(x-4). Anybody for a quick check? Thanks. :D

I was bored... so...

I made my ti-92 solve them against eachother for x.

Your equation yields 4 answers, while the book's answer only yields two answers.

But they are equal in a sense that a solution can be derived from both when set equal to the original polynomial.

When having the ti-92 factor the original, I get:

(2(4x^3+1))/x^2

And simplifies to:

8x+2/x^2

So what kind of question wants a partially simplified solution?

That's silly. :lol:

I had a quiz where the question was to find the factors of 6!/3! or something.

I thought the question was stupid because it has so many possible factors, how far should I go??? (I got it wrong, of course :rolleyes: )

Since 6!/3! is 120, don't you just have to find the factors of that then? 1,2,3,4,5,6,8,10,12...

What is fairly interesting (yeh, rite) is finding the factors of 2003²⁰⁰³... no better yet, find the factors of that number which are perfect squares.

I must be having a mental block, but what are perfect squares?

Quote:

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Originally posted by Acidic
I must be having a mental block, but what are perfect squares?

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Don't know the formal definition, but its basically any number whose square root is an integer, eg 4,9,16,25,36,etc.

I forget the exact wording (it was in french anyways) but the point was to simplify it from

6!/3!

to

6*5*4*3*2*1
------------------
3*2*1

to

6*5*4

and if you had anything else it was wrong

I was wrong. 2x -24 / x(x+4)(x-4) is in fact the correct answer. :blush:

4 / x² + 4x - 2 / x² - 4x

4(x² - 4x) - 2(x² + 4x) / (x²+ 4x)(x² - 4x)

2x² - 24x / (x²+ 4x)(x² - 4x)

2x(x - 12) / x²(x + 4)(x - 4)

2(x - 12) / x(x + 4)( x - 4) --> 2x - 24 / x(x + 4)(x - 4)

I must have originally factored the denom wrong.

The corect breakdown should be --> (x² + 4x)(x² - 4x) --> x(x + 4)x(x - 4) --> x²(x + 4)(x - 4) --> x²(x² - 16) --> x⁴ - 16x² --> (x² + 4x)(x² - 4x)