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At what point

  1. May 31, 2003 #1
    At what point is the tangent to f(x)=x^2 + 4x - 1 horizontal?

    How do you do that? I think it's asking me at what point is x = 0, or undefined, right??
  2. jcsd
  3. May 31, 2003 #2


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    What is the unique feature about the equation of a horizontal line?
    How does that relate to tangent lines?
    Last edited: May 31, 2003
  4. May 31, 2003 #3


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    Horizontal tangent is where derivative=0, that is x=-2.
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