Distributive Law

mathxyz

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Jul 8, 2005
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3(x) times 3(x + 1) times 3(2 - x) =

My answer: -27x^3 + 27x^2 + 54

Am I right?
 

Denis

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Feb 17, 2004
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mathxyz said:
3(x) times 3(x + 1) times 3(2 - x) =
My answer: -27x^3 + 27x^2 + 54
Am I right?
No.
 

Matt

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Jul 3, 2005
Messages
183
mathxyz said:
3(x) times 3(x + 1) times 3(2 - x) =

My answer: -27x^3 + 27x^2 + 54

Am I right?
No, but you are close; the correct answer is -27x<sup>3</sup> + 27x<sup>2</sup> + 54x.
 

mathxyz

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Yes..

Yes, I forgot to include the variable x with 54. I was not off by much.
 

Denis

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Re: Yes..

mathxyz said:
Yes, I forgot to include the variable x with 54. I was not off by much.
Yes Sir; you were most certainly not off by much.
Perhaps the Honorable Guido will give you 100%.
 

~Midnight.Kitten~

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Matt said:
mathxyz said:
3(x) times 3(x + 1) times 3(2 - x) =

My answer: -27x^3 + 27x^2 + 54

Am I right?
No, but you are close; the correct answer is -27x<sup>3</sup> + 27x<sup>2</sup> + 54x.
if you were asked to combine them into like terms, would it be possible with the ^3 and ^2
 

tkhunny

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Cubes and squares are NOT "like" terms.

It must match on all bases and exponents.

x^3 and y^3 No. Same exponent but different bases
x^2 and x^3 No. Same base but different exponents
x*y and x^2 No. Same TOTAL exponent, but not anything else.
x^2*y and x*y^2 No. Same TOTAL exponent, but not anything else.
 

Denis

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-27x^3 + 27x^2 + 54x

All you can do with that, Black Cat, is simplify it a bit:
-27x(x^2 - x - 2)
 

arthur ohlsten

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Feb 20, 2005
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or simplify it to :
-3^3 x (x+1) (x-2)
Arthur
 

mathxyz

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Jul 8, 2005
Messages
112
hey

Great notes for my math files.
 
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