a值的几何意义

GeoGebra 命令及参数

1. Element(sliderList, a) → trueA
2. Point(eq1) → A
3. Point(eq1) → B
4. Point(eq1) → C
5. Point(eq1) → D
6. Point(eq1) → E
7. Point(eq2) → F
8. Point(eq2) → G
9. Point(eq2) → H
10. Point(eq2) → I
11. Point(eq2) → J
12. Point(eq3) → K
13. Point(eq3) → L
14. Point(eq3) → M
15. Point(eq3) → N
16. Point(eq3) → O
17. Segment(I, (x(I), y(F))) → Iseg
18. Segment(E, (x(E), y(A))) → Eseg
19. Segment(D, (x(D), y(A))) → Dseg
20. Segment(N, (x(N), y(K))) → Nseg
21. Segment(O, (x(O), y(K))) → Oseg
22. Segment(J, (x(J), y(F))) → Jseg
23. Midpoint(Iseg) → Imid
24. Midpoint(Jseg) → Jmid
25. Midpoint(Eseg) → Emid
26. Midpoint(Dseg) → Dmid
27. Midpoint(Nseg) → Nmid
28. Midpoint(Oseg) → Omid
29. LaTeX(twoUnitsCaption) → Icaption
30. LaTeX(twoUnitsCaption) → Ncaption
31. LaTeX(twoUnitsCaption) → Ecaption
32. LaTeX("\scriptsize" + (FractionText[abs(trueA)])) → oneUnitCaption
33. Polygon({(-9.5, -13.5), (-9.5, 20.5), (10.5, 20.5), (10.5, -13.5)}) → viewBox
34. LaTeX("\textbf{Instructions: }All three of the parabolas shown have the same \(a\)-value in their equations. \\Change the \(a\)-value and see how it affects the indicated distances.") → INSTRUCTIONS
35. LaTeX("\textbf{Question: }What is the relationship between the value of \(a\) and the shape of the graph?") → QUESTION
36. LaTeX("\text{" + QUESTION + "\\" + INSTRUCTIONS + "}") → TEXT