b***k
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woshigsw (砍砍砍) 于 (Wed Feb 27 16:28:50 2008) 提到:
Three circles of radius of 1,2,3 are in contact with each other. In the gap
between the three circles put one more circle which is also in touch with
all other three circles. What is the radius of the new circle?
I have one way to do it but I am not satisfied with it.
Connect all centers of those circles. The original three circles' centers
form a triangle and this triangle is divided into three small tr |
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