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    Hi! Can anyone help me with this problem? :

    Write in completed square form: 2x²+4x+6

    Please give the step-by-step explanation...

    Thanks!
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    (Original post by Aegyst)
    Hi! Can anyone help me with this problem? :

    Write in completed square form: 2x²+4x+6

    Please give the step-by-step explanation...

    Thanks!
    First take out a factor of 2:

    = 2(x^2 + 2x + 3)

    Then complete the square for x^2 + 2x + 3.

    Please post your working if you're not sure. If you don't know how to complete the square for x^2 + 2x + 3 then let us know.
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    (Original post by Aegyst)
    Hi! Can anyone help me with this problem? :

    Write in completed square form: 2x²+4x+6

    Please give the step-by-step explanation...

    Thanks!
    Whenever you complete the square, the coefficient of the x^2 term must ALWAYS be one. You can do this by taking out a factor of two from the whole equation, then after that you will be left with 2(x^2+2x+3). Then complete the square on x^2+2x+3
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    (Original post by Notnek)
    First take out a factor of 2:

    = 2(x^2 + 2x + 3)

    Then complete the square for x^2 + 2x + 3.

    Please post your working if you're not sure. If you don't know how to complete the square for x^2 + 2x + 3 then let us know.
    Could you please write down the working? I still don't get it... Thanks.
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    (Original post by jaspreetb)
    Whenever you complete the square, the coefficient of the x^2 term must ALWAYS be one. You can do this by taking out a factor of two from the whole equation, then after that you will be left with 2(x^2+2x+3). Then complete the square on x^2+2x+3
    Could you give me the step-by-step working? I don't get it, actually.
    Thanks, by the way!
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    (Original post by Aegyst)
    Could you please write down the working? I still don't get it... Thanks.
    Sorry we can't give full solutions.

    Can you please show us what you've tried? Do you know how to complete the square for (x^2 + 2x + 3)?
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    (Original post by Notnek)
    Sorry we can't give full solutions.

    Can you please show us what you've tried? Do you know how to complete the square for (x^2 + 2x + 3)?
    Is this correct? :

    x²+2x+1 -3+1
    (x+1)² -2
    (x+1)²+2
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    (Original post by Aegyst)
    Is this correct? :

    x²+2x+1 -3+1
    (x+1)² -2
    (x+1)²+2
    That's right.

    So 2(x^2 + 2x + 3)

    is just going to be 2 x this. So you get:

    2[(x+1)²+2]

    Can you expand this to finish it off (i.e. multiply both terms by 2).
 
 
 
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