Intersect - command in CAS & order - bug?

Hellsla shared this problem 4 months ago
Solved

Hi,

If I have defined f: 28x+45y=5119 and c: (x-43)^2+(y-87)^2=11236 and I try to find their points of intersection in GeoGebra Classic 6 the command Intersect(f,c) returns ? and intersect(c,f) returns {(-47,143),(133,31)}. So depending on the order, it depends do I get an answer. Is this a bug? If not should it be written on the manual?

(see the attached file for a screenshot of the situation)

Br, Lauri

Comments (7)

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If not should it be written on the manual? 


manual says

Examples:

    Intersect( <Line> , <Object> ) creates the intersection point(s) of a line and a plane, segment, polygon, conic, etc.
in CAS syntax. So there is a bug

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Terve, Lauri! :)

I'm asking Mike about it. I confirm your report.

Take care!

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{Intersect(28x + 45y = 5119,(x - 43)² + (y - 87)² = 11236)}

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Terve Simona :D

Thanks for the comments!

Here is a screenshot from GeoGebra 6 Classic with the same curves with braces and in different order.

One returns ? and the other returns the intersection point.

/fTTzfHHH2+WLFlShb2nyxCAAAQgAAEIQAAChRBAWCqEXoXWlbjUq1evCu0d3YIABCAAATcB5VXq2bOn+fLLL923eQ8BCEAAAhCAAAQgAIFABBCWAmGqvoemTZtWfZ2mxxCAAASqkIB+30+fPr0Ke06XIQABCEAAAhCAAATCIICwFAZFbEAAAhCAAAQgAAEIQAACEIAABCAAgSokgLBUhYNOlyEAAQhAAAIQgAAEIAABCEAAAhCAQBgEEJbCoIgNCEAAAhCAAAQgAAEIQAACEIAABCBQhQQQlqpw0OkyBCAAAQhAAAIQgAAEIAABCEAAAhAIgwDCUhgUsQEBCEAAAhCAAAQgAAEIQAACEIAABKqQAMJSFQ46XYYABCAAAQhAAAIQgAAEIAABCEAAAmEQ+H8k0aSxFkWlsAAAAABJRU5ErkJggg==

Br, Lauri

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This is GeoGebra 5

4c34de29c2084c29cd47b2600d69d40f

Like mathmagic said it is a bug.

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Will be fixed soon!

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Please try v634

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