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Math Help - three answers for a simple derivative

  1. #1
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    three answers for a simple derivative

    Hi,
    I just did an online test that had the question below. I have no Idea what it was asking. I know that y'= -2x. Although I was not sure why there was three answer boxes layed out like they where and I am even more confused with the answer they gave me at the end of the test.


    Find derivative of y=−x^2+3.
    y′=________ x^2 + __________ x+ ________________ .


    Answer Key: 0, -2, 0 (numeric)


    Can someone please Explain this to me?
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  2. #2
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    Re: three answers for a simple derivative

    Quote Originally Posted by Kristy View Post
    Hi,
    I just did an online test that had the question below. I have no Idea what it was asking. I know that y'= -2x. Although I was not sure why there was three answer boxes layed out like they where and I am even more confused with the answer they gave me at the end of the test.


    Find derivative of y=−x^2+3.
    y′=________ x^2 + __________ x+ ________________ .


    Answer Key: 0, -2, 0 (numeric)


    Can someone please Explain this to me?
    wow. Maybe you should switch to a more difficult course or something.

    What they have done is give you place holders for the coefficients of a quadratic polynomial.

    As you noted $y'=-2x$ this is

    $0\cdot x^2 + (-2)x+0$ hence your 3 coefficients (0,-2,0)
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  3. #3
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    Re: three answers for a simple derivative

    Oh, I see, Thanks so much for your very prompt answer.
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  4. #4
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    Re: three answers for a simple derivative

    Quote Originally Posted by Kristy View Post
    Hi,
    I just did an online test that had the question below. I have no Idea what it was asking. I know that y'= -2x. Although I was not sure why there was three answer boxes layed out like they where and I am even more confused with the answer they gave me at the end of the test.


    Find derivative of y=−x^


    Can someone please Explain this to me?
    Romsek answered while I was fiddling
    Last edited by JeffM; March 21st 2014 at 05:20 PM. Reason: too late Romsek answered it already
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