乘法的交换律

GeoGebra 命令及参数

1. If(a < 4, 2, If[a < 7, 1.5, 1]) → Ax
2. If(b < 4, 2, If[b < 7, 1.5, 1]) → Ay
3. If(a < 4, 2, If[a < 7, 3.5, 5]) → da
4. If(b < 4, 2, If[b < 7, 3.5, 5]) → db
5. If(da / a < db / b, da / a, db / b) → dis
6. If(a < 4, 2, If[a < 7, 1.5, 1]) → By
7. Sequence(Segment[A + (j * (A2 - A) / a), A4 + (j * (A2 - A) / a)], j, 0, a) → list1
8. Sequence(Segment[A + (j * (A4 - A) / b), A2 + (j * (A4 - A) / b)], j, 0, b) → list2
9. Sequence(Segment[B + (j * (B2 - B) / b), B4 + (j * (B2 - B) / b)], j, 0, b) → list3
10. Sequence(Segment[B + (j * (B4 - B) / a), B2 + (j * (B4 - B) / a)], j, 0, a) → list4
11. Polygon(A, A2, A3, A4) → poly1, a_1, a2, a3, a4
12. Polygon(B, B2, B3, B4) → poly2, b_1, b2, b3, b4