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You are not logged in. #1 20060511 23:37:18
a chair problemShow that a chair with four equal legs can be positioned so that all its legs are in contact with the floor. #2 20060512 01:00:18
Re: a chair problemdoraeyee_u_v, Character is who you are when no one is looking. #3 20060512 05:23:48
Re: a chair problemIf the seat is flat and the legs are the same length then there exists room to make a perfect chair and an imperfect chair. igloo myrtilles fourmis #5 20060513 01:20:34
Re: a chair problemThe following are assumed: And let all four legs be of length L. The normal to the plane is (A, B, C). Also, let the position where each leg intersects the plane be: The unit normal of the plane is: As so the normal of length L (the lenght of the leg is: So the position of the feet of the chair will be at: And it's the same idea for L2, L3, and L4. All of these points can be placed into the plane: So the bottom of all four legs are in that plane, which we call the "floor". "In the real world, this would be a problem. But in mathematics, we can just define a place where this problem doesn't exist. So we'll go ahead and do that now..." #6 20060513 02:02:30
Re: a chair problemWhat's a unit normal? Just wondering. igloo myrtilles fourmis #8 20060514 10:24:10
Re: a chair problemthank you very much ricky, this is very clear and i understand it 