Assignment 7

Problems 1,2

Cristina Aurrecoechea

Fall 2005


Given two circles and a point on one of the circles, we construct a circle tangent to the two circles with one point of tangency being the designated point. This file contains the basic construction, shown in Figure 1. The tool obtains the tangent circle (in blue) to two given circles, given a point in one of the circles.

Figure 1



The tool works independently of where is the point of tangency. It can be in either circle, as shown in Figure 2.

Figure 2


And it covers any case: circles being disjoint, overlapping or containing each other, as shown in Figure 3.


Figure 3


Next we augment the previous construction to calculate the two existing tangent circles. Check this file.

Figure 4

The tool is valid for any P point of tangency and any two circles.

Figure 5


Finally we look at the traces of centers of the tangent circles as the point of tangecy moves. Check this file.

Figure 6






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