Dynamic Illustration of Similar Circles

Dynamic Illustration of Similar Circles
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2019-05-21 21:16
This example demonstrates to students that all circles are similar through dynamic illustration. It involves core math concepts like circles, similarity transformation, and geometric construction. The construction uses commands/objects such as Circle, Point, Segment, Dilate, Vector, Translate, and Intersect in GeoGebra. Suitable for high school students to understand circle similarity and transformation applications.

GeoGebra Commands & Parameters

  1. Circle(A, B) → c
  2. Circle(C, D) → d
  3. Point(c) → E
  4. Point(d) → F
  5. Segment(A, E) → a
  6. Segment(C, F) → b
  7. Dilate(C, If[0 < a_1 ≤ 1, 1 - a_1, 0], A) → C'
  8. Vector(C, C') → u
  9. Translate(d, u) → d'
  10. Translate(C, u) → C'_1
  11. Translate(C, u) → C'_2
  12. Translate(F, u) → F'
  13. Segment(C'_2, F') → g'
  14. Intersect(h, a, 1) → G
  15. Dilate(G, If[2 < a_1 ≤ 3, 3 - a_1, 0], E) → G'
  16. Circle(A, G') → k

AI Drawing Prompt Reference

Draw two circles c and d, then pick point E on circle c and point F on circle d. Connect AE and CF. With A as the center and AE as the radius, draw circle c'. With C as the center and CF as the radius, draw circle d'. Then, starting from A, draw vector u in the direction of AE, and translate circle c' by vector u to get circle c''. Translate point C by vector u to get C'1 and C'2. Draw line segment g' from C'2 to F'. Find the intersection of line segment AE and circle c', name it G, and draw circle k with E as the center and EG as the radius.
The prompt above was compiled from the original drawing commands and is for reference only.