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You need to inscribe the Steiner inellipse.
I read about Steiner inellipse but i don't figure out how to solve that problem. Triangle's area could be found by Heron formula and the Elipse area is pi/(3 sqrt(3)) of that one. Elipse area beside could be calculated as pi*a*b where a is major semi-axis and b minor semi-axis. Steiner inellipse say that the elipse is tangent at the middel point of the three sides. The center of the Elipse is the baricenter of the triangule.
Please help. Thanks
I can teach you my dear ~~~~^_^
You can use coordinate transformation to get equilateral triangle from the given, and according to sample the answer for equilateral triangle is circle. As I remember, this task or similar was discussed in CF recently.
Coordinate transformation? Where do i can read about ir? thanks
Any book about linear algebra.
There is a way to find focuses of Steiner ellipse: Marden's_theorem. After that you can find R, for example, from this fact: Steiner ellipse is tangent to the sides of triangle at their midpoints. Simply put midpoint of any side into ellipse equation.