toughest geometry problem?
485045
Let a(P,Q) be the direction angle of the vector going from point P to Q measured counterclockwise from AB (so that a(A,B)=0). Then the direction angles of the bisectors going through B and C respectively are:\n\na(B,C)/2\n(a(B,C)-pi+a(A,C))/2\n\nand the angle between the two (A1)\n\nA1 = a(B,C)/2 - (a(B,C)-pi+a(A,C))/2 = pi/2 - a(A,C)/2\n\nIn terms of the original angle at A (which is a(A,C)) this is:\n\nA1 = pi/2 - A/2\n\nThat is, the recursion relation is:\n\nA_(n+1) = pi/2 - A_n/2\n\nSubstituting A_n = pi/3 + X_n, gives:\n\nX_(n+1) = - (1/2)*X_n\n\nSo clearly X_n = (-1/2)^n * Constant\n-->\nA_n = pi/3 + (-1/2)^n * Constant\n\nSince A_0 = A , the constant is: A-pi/3\n\n--> answer 4\n\nTo guess the answer without doing any work, just note that A_0 must be A, so only 3 and 4 are eligible. It's easy to see A_n can't be a constant just by sketching a triangle with a very obtuse angle at A.
686004
Hell, yes. Proofs = ack! Anyone who says geometry is "easy" is lying. Even if you do good in it, it's still not "easy" for a high schooler.
513219
Perfect Squares\n\nEdit: First Four to be precise
1121982
look std 10 th NCERT mathematics text book... its in the part 2 of  mathematics in geometry section.
736970
Here are some real tough ones.(Looked tough to me)\n\nProve that cot(90 - theta)sin(90 - theta) = sin theta\n\nFind Cos(3x)\n\nFind Sin(3x)
116787
Euclid! Come and help us please!!
403281
take a straw (cylinder) and ram it through a potato.  If you do it right, the straw will go right through the potato!  The cylinder is the strongest and most stable of the shapes and you can see why soups, veggies, fruits, etc. all come in cans!\n\nRight triangels, or right angles are all around you.  The floor and the wall of you room for example.  The bottom of a pool is a good example of an obtuse triangle, suspension bridges - trapezoid, if you look at the tip of a pencil - it's a cone but the shape of a cone when you look at it head on is a scalene triangle
670024
plano concave\nconvexo concave\nconvergent
397113
sphere, elliptic, plane, euclidean, pseudosphere, hyperbolic
663345
I don't think there is an easy answer to the Alexandia Cornice problem.\n\nSorry.
208250
The neat thing about geometric optimization is that the optimum shapes are always a perfect square, circle, triangle, sphere, etc. depending on what shape you are working with. In this case, a perfect half sphere with a 8m radius would hold the most water for the given surface area.
33162
Check Out This Website!! \n\nGives You Examples And Everything!! \n\nhttp://www.mathleague.com/help/geometry/geometry.htm
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Without the knowledge of where point e is, this problem is insolvable.\n\nI suspect, however, from a brief diagramming session, that you will need to solve for the length of ab using the Pythagorean Theorem, and set up similar triangles.
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Trigonal planar.\n\n120 degrees.
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tetracontaheptagon\n\nhttp://en.wikipedia.org/wiki/Polygon\n\ncheck ya later ♥
928210
The best way to attack proving problems in geometry is to answer and answer more proving related problem. No one can help to solve a problem. No one can help you speed up how you solve. It's you who can do that.\n\nMost of my classmates want to be good in algebra.\nBut they hate to solve algebraic proble,.\nI told them to try  answering all the questions and exercises in a book of algebra. At first, they did not believe what I have told them. Until they realize that they are becoming better and better in attacking problems in algebra.\n\nSo i think, it's up tp you if you will be good in proving geometric relations.\nI have also done it myself.\nAnd i can't believe believe that i can answer a problem with ease. It only took me a few second to answer a problem that my classmates took lots of minutes to answer.\n\nBelieve me. Solve and solve lots of problem. And you will soon realize that you will solve difficult problems with ease.
1017007
Ive noticed you were asking quite alot of these geometry questions. I think you should pay more attention in class and you wouldnt need to ask home work questions, and plus, just knowing the answer wont help, youll have to know how to do it, especially if this is for a final exam...