无字证明：0到pi/2之间sin(x)的积分

GeoGebra 命令及参数

1. Polygon(I, J, 4) → poly1, g, h, i, j, K, L
2. Sequence(Translate[I, Vector[(i * Vector[I, J])]], i, 0, 1, 1 / n) → l2
3. Midpoint(K, I) → N
4. Join(Sequence[Rotate[l2, i, N], i, 0, (2 * π), (2 * π / 4)]) → l3
5. Sequence((i, f(i)), i, 0, π / 2, 1 / n) → l1
6. Sequence(Translate[M, Vector[(i * Vector[M, O])]], i, 0, 1, 1 / 16) → l1b
7. Sequence(Translate[O, Vector[(i * Vector[O, (0, 0)])]], i, 0, 1, 1 / 20) → l1c
8. Join({l1, l1b, l1c}) → l6
9. Sequence(Vector[Element[l6, i], Element[l3, i]], i, 1, Length[l3]) → l4
10. Sequence(Translate[Element[l6, i], Vector[(Animation / 10 * Element[l4, i])]], i, 1, Length[l6]) → l5
11. Polygon(A, B, C, D) → poly4, a, b, c, d
12. Integral(f, 0, 1.5707963267948966) → e
13. Point(poly4) → E
14. Polygon(l5) → poly2
15. Length(l3) → l
16. Length(l6) → k
17. Vector((0, 0), I) → u
18. Polygon(P, E, 4) → poly3, m, q, r, s, Q, R
19. Translate(poly3, Vector[(Animation / 10 * u)]) → poly3'
20. PolyLine(l5) → t
21. Centroid(poly3') → S
22. Line(S, yAxis) → f_1
23. Intersect(f_1, poly3') → T, U
24. Line(S, xAxis) → g_1
25. Intersect(g_1, poly3') → V, W
26. Vector((0, 0), (0, 1.2)) → v
27. Vector((0, 0), (2.15, 0)) → w
28. Midpoint(P, O) → Z