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Interactive resource

Apollonius circle applications

Geometry. On a circle, construct M so k·PB becomes PM; minimize PA + k·PB. Free interactive GeoGebra resource — adjust parameters in the browser.

  • Circles
  • Extrema

Overview

On a circle, construct M so k·PB becomes PM; minimize PA + k·PB.

Explanation

When P lies on a fixed circle and you minimize PA + k·PB, build M with PM = k·PB.
Then PA + k·PB = PA + PM — a path from A to the circle to M.
Finish with straight-line/circle geometry or reflection.

How to use

Drag P on the circle; dashed AM meets the circle at the optimum.

Knowledge points

  • Circles
  • Extrema