Descartes' circle theorem | Soddy's formula (Engelsk)
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Definition
If we draw four circles A, B, C, D so that they do not overlap but each touches the other three, and if we call the radii of the circles r1, r2, r3, r4, and let b1=1/r1, etc, then ( b1 + b2 + b3 + b4 ) 2 = 2 ( b1 2 + b2 2 + b3 2 + b4 2 ).
Relations
- bredere:
- (en) Theorem
- referencer:
- (en) Circle
- (en) Radius
- se også:
- (en) Apollonius' problem
Støttet af: