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Math Help - Roots and points on a graph?

  1. #1
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    Roots and points on a graph?

    Suppose that F(0)=-2 and F(2)=0
    a) Which of the four points (0,-2), (-2,0) (2,0), (0,2) must be on the graph of F?

    b) Does F have a root at 0? Justify.

    c) Does F have a root at x=2? Justify.

    For these answers I got:

    a) (-2,0)

    b) Yes at x=-2. This is because of the coordinates (-2,0)

    c) Yes at x= 2 this is because of the coordinates (2,0)

    Are these answers correct?
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  2. #2
    Super Member Aryth's Avatar
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    b) is only half right.

    The answer is yes not because of the point (-2,0), but because of the point (2,0).

    F(0) = -2 provides the point (0, -2) not (-2, 0).
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  3. #3
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    Quote Originally Posted by Aryth View Post
    b) is only half right.

    The answer is yes not because of the point (-2,0), but because of the point (2,0).

    F(0) = -2 provides the point (0, -2) not (-2, 0).
    Why would the answer to b) be yes? f(0) \neq 0 so x=0 is not a root :X
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  4. #4
    Super Member Aryth's Avatar
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    You're right. I misread b). The answer is no.
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