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Math Help - Problem Inside

  1. #1
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    Post Problem Inside

    Hello People. Im new hence the 1 post.

    I have a problem, i recived some questions that i carnt work out, ive read books but cannot get it.

    Here are so examples of problems:


    Multipy:

    A: (3x+3)(9x-2)

    2 2
    B: (x +3x)(4x -1.5x+2)

    (x is squared and 4x is squared)

    -1 -0.5 2
    C: (x + 6x)(3+x +2x

    (x with -1 at the top and 3+x with -0.5 at the top of, 2x squared.)


    Can anyone work those out, and show the steps please, much appriciated.
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  2. #2
    Bar0n janvdl's Avatar
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    Quote Originally Posted by ForgottenMemorie View Post
    Hello People. Im new hence the 1 post.

    I have a problem, i recived some questions that i carnt work out, ive read books but cannot get it.

    Here are so examples of problems:


    Multipy:

    A: (3x+3)(9x-2)

    2 2
    B: (x +3x)(4x -1.5x+2)

    -1 -0.5 2
    C: (x + 6x)(3+x +2x


    Can anyone work those out, and show the steps please, much appriciated.
    Welcome to the forum!

    A) (3x+3)(9x-2)
    = (3x \times 9x) + (3x \times -2) + (3 \times 9x) + (3 \times -2)
    = 27x^2 - 6x + 27x - 6
    = 27x^2 + 21x - 6

    Can you finish the rest now?
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  3. #3
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    Last bit = 48x^2 - 6 ?

    I'll try the rest using hte same principal. I'll be back if i get stuck.

    Thanks for the help.
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  4. #4
    Bar0n janvdl's Avatar
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    Quote Originally Posted by ForgottenMemorie View Post
    Last bit = 48x^2 - 6 ?

    I'll try the rest using hte same principal. I'll be back if i get stuck.

    Thanks for the help.
    No, remember that you can't add variables with different exponents.
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  5. #5
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    Is 27x^2+21x-6 the final answer? I have tried for very long time now (month).

    Can someone help Multiply with another question please.
    This is urgent.

    (x^2+3x)(4x^2-1.5x+2)

    (x-^1+6x)(3+x-^0.5+2x^2

    1 is ^ 0.5 is ^
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  6. #6
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    Is 27x^2+21x-6 the final answer?
    Yes.

    (x^2+3x)(4x^2-1.5x+2)
    (x^2+3x)(4x^2-1.5x+2) = x^2(4x^2-1.5x+2)+3x(4x^2-1.5x+2)
    =x^24x^2+x^2(-1.5x)+x^22+3x4x^2+3x(-1.5x)+3x2

    I think you can continue from here.

    To get more than one character in a superscript put {} around what you want at the top eg x^{potato salad tastes better than fish} produces x^{potatosaladtastesbetterthanfish}
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  7. #7
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    Is that the answer?

    x^4  4+21x^3/2-2.5x^2+6x

    how to do 6 with Math tags?
    ...................7

    l
    l
    l
    V



    Im stuck on (x^{-1}+6x)(3+x^{-0.5}+2x^2

    I need to multiply it out.
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  8. #8
    GAMMA Mathematics
    colby2152's Avatar
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    Well, let's work out what badger provided:

    x^24x^2+x^2(-1.5x)+x^22+3x4x^2+3x(-1.5x)+3x2

    4x^4+-1.5x^3+2x^2+12x^3-4.5x^2+6x

    4x^4+10.5x^3-2.5x^2+6x

    It looks like you are right!

    Now, on to your other problem...

    (x^{-1}+6x)(2x^2+x^{-0.5}+3)

    x^{-1}(2x^2+x^{-0.5}+3) + 6x(2x^2+x^{-0.5}+3)

    2x+x^{-1.5}+3x^{-1}+12x^3+6x^{1.5}+18x

    2x^3+6x^{1.5}+20x+3x^{-1}+x^{-1.5}+1
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  9. #9
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    how to do 6 with Math tags?
    ...................7
    Use \frac {numerator}{denominator} to get \frac {numerator}{denominator}
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