有向数的乘法

GeoGebra 命令及参数

1. Segment((x(L), y(L) + 2), (x(U), y(U) - 2)) → f
2. Vector(L, (x(L), y(L) + 20)) → u
3. Point(f) → B
4. If(x(B) - x(A) > 0, "+", "") → sign2
5. If(x(B) - x(A) < 0, "+", "") → sign3
6. If(x(A) > 0, "+", "") → signa
7. If(x(B) - x(A) > 0, "+", "") → signba
8. If(x(B) > x(A), "+", "-") → op2
9. If(x(B) > 0, "+", "") → signb
10. Corner(1) → C
11. Vector((x(L), y(L) + 20), L) → v
12. Sequence(Segment[(x(L) - 0.3, y(L) + (2 * k)), (x(L) + 0.3, y(L) + (2 * k))], k, 1, 9) → l7
13. Sequence((x(L) - 0.3, y(L) + (2 * k)), k, 1, 9) → l8
14. Sequence(Semicircle[(x(A) + 0.5, (k * dis) + y(A)), (x(A) + 0.5, ((k - 1) * dis) + y(A))], k, 1, Div[y(B) - y(A), dis]) → l1
15. Sequence(Semicircle[(x(A) + 0.5, ((1 - k) * dis) + y(A)), (x(A) + 0.5, ((-k) * dis) + y(A))], k, 1, Div[y(A) - y(B), dis]) → l3
16. Sequence(Vector[(x(A) + 1, (k * dis) + y(A) + 0.1), (x(A) + 0.4, (k * dis) + y(A))], k, 0, Div[y(B) - y(A), dis] - 1) → l5
17. Sequence(Vector[(x(A) + 1, (k * dis) + y(A) - 0.1), (x(A) + 0.4, (k * dis) + y(A))], k, 1, Div[y(B) - y(A), dis]) → l2
18. Sequence(Vector[(x(A) + 1, ((-k) * dis) + y(A) - 0.1), (x(A) + 0.4, ((-k) * dis) + y(A))], k, 0, Div[y(A) - y(B), dis] - 1) → l4
19. Sequence(Vector[(x(A) + 1, ((-k) * dis) + y(A) + 0.1), (x(A) + 0.4, ((-k) * dis) + y(A))], k, 1, Div[y(A) - y(B), dis]) → l6
20. If(SelectedIndex[l9] ≟ 2, "rise", If[SelectedIndex[l9] ≟ 3, "drop", ""]) → text0
21. If(n > 0, "later", "ago") → text1
22. If(n' ≟ 1, "minute", "minutes") → textp
23. Vector(D, E) → w