圆方程快速复习：解析几何中的圆与圆心

GeoGebra 命令及参数

1. Circle(B, A) → c
2. Point(c) → C
3. Intersect(eq1, f) → D
4. Polygon(B, D, C) → t1, c_1, b, d
5. Angle(C, D, B) → α
6. Dilate(B, If[0 < a ≤ 1, 1 - a, 0], D) → B'
7. Segment(B, B') → g
8. Dilate(D, If[1 < a ≤ 2, 2 - a, 0], C) → D'
9. Segment(D, D') → m
10. RotateText(text2, pi / 2) → text3
11. Distance(B, A) → o
12. Dilate(C, If[2 < a ≤ 3, 3 - a, 0], B) → C'
13. Segment(C, C') → p
14. Angle(D, B, C) → β
15. Point(c) → E
16. Segment(B, E) → q
17. SurdText(Distance[A, B]) → text6
18. RotateText(text7, β) → text5
19. Circle(B_{1}, A_{1}) → c_{2}
20. Distance(B_{1}, A_{1}) → o_{1}