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Geometry Stumper
02-25-2019, 06:05 AM
Post: #26
RE: Geometry Stumper
PHP Code:
= {1Tan[t2/2]}; 
= {Tan[t2/2Tan[t3/2], Tan[t2/2] + Tan[t3/2]}; (* excircle center *) 

This prove is even shorter !

Dot[c, e-c] = 1 * -tan(t2/2) tan(t3/2) + tan(t2/2) * tan(t3/2) = 0

-> OCE is right triangle -> by symmetry, OCD also right triangle -> CDE is straight line Smile
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Messages In This Thread
Geometry Stumper - Albert Chan - 08-14-2018, 01:45 PM
RE: Geometry Stumper - Thomas Puettmann - 08-14-2018, 06:04 PM
RE: Geometry Stumper - Albert Chan - 08-14-2018, 06:58 PM
RE: Geometry Stumper - Thomas Puettmann - 08-14-2018, 08:35 PM
RE: Geometry Stumper - Albert Chan - 08-15-2018, 12:39 AM
RE: Geometry Stumper - Voldemar - 08-15-2018, 06:38 AM
RE: Geometry Stumper - Albert Chan - 08-15-2018, 11:14 AM
RE: Geometry Stumper - Voldemar - 08-15-2018, 11:56 AM
RE: Geometry Stumper - Albert Chan - 08-15-2018, 12:29 PM
RE: Geometry Stumper - Voldemar - 08-15-2018, 01:16 PM
RE: Geometry Stumper - Albert Chan - 08-15-2018, 07:57 PM
RE: Geometry Stumper - Thomas Puettmann - 08-15-2018, 07:29 AM
RE: Geometry Stumper - jwhsu - 08-16-2018, 12:30 AM
RE: Geometry Stumper - Albert Chan - 08-15-2018, 02:55 PM
RE: Geometry Stumper - Albert Chan - 08-15-2018, 07:23 PM
RE: Geometry Stumper - Thomas Puettmann - 08-16-2018, 04:04 PM
RE: Geometry Stumper - Paul Dale - 08-17-2018, 06:29 AM
RE: Geometry Stumper - brickviking - 08-21-2018, 12:01 AM
RE: Geometry Stumper - Thomas Puettmann - 08-15-2018, 09:46 PM
RE: Geometry Stumper - Albert Chan - 08-15-2018, 11:02 PM
RE: Geometry Stumper - Thomas Puettmann - 08-16-2018, 08:26 AM
RE: Geometry Stumper - Albert Chan - 08-16-2018, 06:46 PM
RE: Geometry Stumper - Albert Chan - 09-03-2018, 01:59 PM
RE: Geometry Stumper - Albert Chan - 10-04-2018, 07:58 PM
RE: Geometry Stumper - Albert Chan - 02-24-2019, 02:37 PM
RE: Geometry Stumper - Albert Chan - 02-25-2019 06:05 AM



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