Curve intersection is not defined

王贵军 shared this question 2 years ago
Answered

Use the command to find the intersection of the curve, the result is not defined

Files: tp.jpg

Comments (5)

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Defining the curves in your definition separately as functions, you can see that indeed there's no intersection.

In this case I think working with functions is easier than using curves: f(x)=Function[cos(x), 0, pi]

chris0fadba09f6fe64e290f237db3fa06ad3

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hello

there is a bug

saludos

Files: foro.ggb
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  1. Intersect[ <Function>, <Function>, <Start x-Value>, <End x-Value> ]


does numeric search so can't always find the intersection


Try


  1. f(x) = sqrt(1 - x²)
  2. g(x) = sqrt(1 - (x - 1)²)
  3. Intersect[f, g, 0, 1]

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yes, it works/Wl4PE+m7bsA0c36rwz4XjP8MU7ijPDCzSAAAAAElFTkSuQmCC

but the help of intersect says

  1. Intersect[ <Curve 1>, <Curve 2>, <Parameter 1>, <Parameter 2> ]Finds one intersection point using a numerical, iterative method starting at the given parameters.

    Example:

    Let a = Curve[cos(t), sin(t), t, 0, π] and b = Curve[cos(t) + 1, sin(t), t, 0, π].

    Intersect[a, b, 0, 2] yields the intersection point A = (0.5, 0.87).


saludos

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  1. does numeric search so can't always find the intersection


... but in this case it is actually a bug. Fixed for next release (5.0.333.0)

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