A circle that seeks tangency with a given circle.
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Tangency Problem of Appolonius
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[*]Geometric Solution: [url]http://www.geogebratube.org/material/show/id/34645[/url]
[*]Differential Solution:
[b]→a.Seek model (one circle)[/b]
b. Solution, v.1: [url]http://www.geogebratube.org/material/show/id/34855[/url]
c. Solution v.2, improved: [url]http://www.geogebratube.org/material/show/id/35386[/url]
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