Two Pole Optimization Problem

This GeoGebra applet is simulation of two poles problem. Two poles are fixed on the ground. The problem is to find string of least length which is tied at the top of two poles and is to be anchored on the ground, somewhere between the two poles. For more on optimization technique check my online book "Flipped Classroom Calculus of Single Variable" https://versal.com/learn/vh45au/
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