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Math Help - Prove

  1. #1
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    Prove

    Hello

    I need to prove this and im having som trouble doing it.


    x(x(x-2)-(x-2)) = x(x-2)(x-1)

    Thank you for any assistance.
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  2. #2
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    x\left[x{\color{red}(x-2)}-{\color{red}(x-2)}\right]

    Focus on the inside expression. Factor the red out to get your desired answer.

    If it helps, imagine a = {\color{red}(x-2)}.

    We then have: x[x{\color{red}a} - {\color{red}a}] = x[{\color{red}a}(x-1)]
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  3. #3
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    Hello, Mladen1!

    I need to prove this and I'm having some trouble doing it.

    . . x[x(x-2)-(x-2)] \:= \:x(x-2)(x-1)
    Exactly what is stopping you?



    [1] Multiply out both sides and show that they are equal! . . . Duh!



    [2] Or we can factor the left side . . .

    . . x\bigg[x\underbrace{(x-2)} - \underbrace{(x-2)}\bigg]
    . . . . .
    common factor
    . . . . . . . \downarrow . . \swarrow
    . . = \quad\;\; x(x-2)(x-1)


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