A seemingly easy logical question

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The discussion revolves around a logical puzzle involving connecting three circles to three triangles without crossing lines, achieving a total of nine connections. Participants express difficulty in solving the puzzle, with one noting they have managed eight connections but not the ninth. The conversation highlights the inherent challenges of the task, including the creation of separate areas that complicate the connections. A suggestion is made to visualize the problem on a toroidal surface, which may provide a different perspective for finding a solution. The overall consensus is that the puzzle is more complex than it initially appears.
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This looks like an easy one, but I haven't found anyone yet who has answered it correctly, including me...
So, the goal is (like shown in the picture), to connect all three circles to each of the three triangles (nine connections in total, i have managed eight). Give it a try. You can go around the triangles and circles with the lines, just as long as they DON'T cross.

∆ ∆ ∆

O O O
 
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What picture?
 
It's impossible. Let's call the triangles T1, T2, T3 and the circles C1, C2, C3. There will be a separated area on each side of the lines going from T1 to C1 to T2 to C2. Let's call one of these areas Ž and the other Đ. There will also be a line going from C1 to T3 to C2, subdividing one of the areas, let's say Đ, into two new areas, one touching T1 which we will call Æ and one touching T2 which we will call Ø, giving a total of three separated areas. T3 now neighbours areas Æ and Ø, T1 neighbours Ž and Æ and T2 neighbours Ž and Ø. No matter which of these areas C3 is in, only one of the points T1, T2 and T3 will be on the edge of this area.
 
See attached gif.
 

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Martin Rattigan said:
See attached gif.

You could also do it in "two dimensions" on the surface of a torus (donut).
 
I was reading documentation about the soundness and completeness of logic formal systems. Consider the following $$\vdash_S \phi$$ where ##S## is the proof-system making part the formal system and ##\phi## is a wff (well formed formula) of the formal language. Note the blank on left of the turnstile symbol ##\vdash_S##, as far as I can tell it actually represents the empty set. So what does it mean ? I guess it actually means ##\phi## is a theorem of the formal system, i.e. there is a...
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