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Completing square HELP

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    There's this question on completing square. 2x^2+2x. My final answer was 2(x+1/2)^2+2/4 but in my textbook the answer was 2(x+1/4)^2*1/2 .???
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    You are correct, you are aware that 2/4 is the same as 1/2 ?
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    (Original post by B_9710)
    You are correct, you are aware that 2/4 is the same as 1/2 ?
    Yes but look inside the brackets my answer is a 1/2 but the textbooks answer was 1/4.
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    Multiply out your answer and the book's and whichever gets to the original question is correct.

    Textbooks can be wrong, remember =)
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    (Original post by bstone13)
    Multiply out your answer and the book's and whichever gets to the original question is correct.

    Textbooks can be wrong, remember =)
    Your textbook is wrong - I've worked it through and I agree with your answer.

    Assuming you meant +1/2 rather than *1/2, it give 2x^2 +x -3/8. Your answer reverts back to the original expression.
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    (Original post by bstone13)
    Your textbook is wrong - I've worked it through and I agree with your answer.

    Assuming you meant +1/2 rather than *1/2, it give 2x^2 +x -3/8. Your answer reverts back to the original expression.
    Thank you so much .I was getting worried ! I don't know how many times I redid that question and watching videos non stop to finally realise I we right. Thank you
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    (Original post by ShikaMekiFuka)
    Thank you so much .I was getting worried ! I don't know how many times I redid that question and watching videos non stop to finally realise I we right. Thank you
    You're welcome - just remember that the textbooks don't always have it right. Ask your teacher if you get stuck too
 
 
 
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