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I have question related to circle-packing. The problem is to find the circle of minimum radius enclosing four non-overlapping circles of arbitrary radius. I have to write a program in C for this question but have not been able to find a formula for the radius of the enclosing circle. Any help appreciated.

For more understanding see this link

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This question is not clear. – Lepidopterist Mar 9 '12 at 16:55
Question is just find the minimum radius of Circle circumscribing four circle of unequal radius. Please see this link for figure and some solution...But required a short approach/formula... – Avinash Singh Mar 9 '12 at 17:03
@jaywendt..Plz help me.. – Avinash Singh Mar 9 '12 at 17:10
Regarding your "test cases": how can even one circle of radius 2500 be contained in a circle of radius 1837? I looked at the link you posted. To make sense of your question I think the radius of the enclosed circles would have to be smaller. – daniel Mar 9 '12 at 18:51
@daniel..Yes ur right..Test case are wrongly posted... – Avinash Singh Mar 9 '12 at 18:54

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