分数除法2:p/q ÷ b 的分治表示法
几何画板及绘图内容加载中,请稍等……
所属专题
Primary School Mathematics Collection
Division of Fractions
Division of Fractions
Division of Fractions
Fraction Division
Fraction Division
该示例展示了如何通过分治法理解分数除法 p/q ÷ b 的几何意义。涉及的核心概念包括分数除法、分数乘以倒数、除数 b 的倒数,以及线性函数表示除法过程。GeoGebra 中使用了 Segment、Point、Sequence、Polygon 等命令,以及 GCD 对象来构造可视化模型,展示除法步骤。该示例适合初中和高中的数学教师和学生使用,特别适用于直观理解分数除法的概念,并通过交互式动态图形进行教学。
GeoGebra 命令及参数
Segment(A, (x(A) + 1, y(A))) → l1Point(Segment[(x(A), y(A)), (x(A) + 1, y(A))]) → PSegment(B, (x(B) + 1, y(B))) → l2Point(Segment[(x(B) + 2 / 6, y(B)), (x(B) + 1, y(B))]) → QPoint(Segment[(x(C) + 1 / 6 - 0.005, y(C)), (x(Q) - 1 / 6, y(C))]) → RSegment(C, (x(C) + 1, y(C))) → l3Sequence(Circle[((2.5 * (i - 1)), 0), 1], i, 1, a) → list1Sequence(Sequence[CircleSector[((f * sin((((2 * k) - 1) * θ / 2))) + (2.5 * (m - 1)), (f * cos((((2 * k) - 1) * θ / 2)))), ((f * sin((((2 * k) - 1) * θ / 2))) + sin((k * θ)) + (2.5 * (m - 1)), (f * cos((((2 * k) - 1) * θ / 2))) + cos((k * θ))), ((f * sin((((2 * k) - 1) * θ / 2))) + sin(((k - 1) * θ)) + (2.5 * (m - 1)), (f * cos((((2 * k) - 1) * θ / 2))) + cos(((k - 1) * θ)))], k, 1, b], m, 1, a) → list4Sequence(CircleSector[(((-1 * f) * sin((((2 * k) - 1) * θ / 2))) + (2.5 * a), (f * cos((((2 * k) - 1) * θ / 2)))), (((-1 * f) * sin((((2 * k) - 1) * θ / 2))) - sin(((k - 1) * θ)) + (2.5 * a), (f * cos((((2 * k) - 1) * θ / 2))) + cos(((k - 1) * θ))), (((-1 * f) * sin((((2 * k) - 1) * θ / 2))) - sin((k * θ)) + (2.5 * a), (f * cos((((2 * k) - 1) * θ / 2))) + cos((k * θ)))], k, 1, c) → list5CircleSector(((2.5 * a), 0), ((2.5 * a), 1), ((2.5 * a) - sin((c * θ)), cos((c * θ)))) → s1Sequence(Segment[((2.5 * a), 0), ((2.5 * a) - sin((j * θ)), cos((j * θ)))], j, 1, c - 1) → list2Sequence(Segment[((2.5 * a), 0), ((2.5 * a) - sin((j * θ)), cos((j * θ)))], j, c + 1, b - 1) → list3CircleSector(((2.5 * a), 0), ((2.5 * a) - sin((c * θ)), cos((c * θ))), ((2.5 * a), 1)) → s2Segment(D, (x(D) + 1, y(D))) → l4Point(Segment[(x(D) + 2 / 5, y(D)), (x(D) + 1, y(D))]) → SSequence(Sequence[CircleSector[(((-1 * f) * sin((((2 * k) - 1) * θ / 2))) + (2.5 * (m - 1)), (f * cos((((2 * k) - 1) * θ / 2)))), (((-1 * f) * sin((((2 * k) - 1) * θ / 2))) - sin(((k - 1) * θ)) + (2.5 * (m - 1)), (f * cos((((2 * k) - 1) * θ / 2))) + cos(((k - 1) * θ))), (((-1 * f) * sin((((2 * k) - 1) * θ / 2))) - sin(((k - 1) * θ) + θ / d) + (2.5 * (m - 1)), (f * cos((((2 * k) - 1) * θ / 2))) + cos(((k - 1) * θ) + θ / d))], k, 1, b], m, 1, a) → list6Sequence(CircleSector[(((-1 * f) * sin((((2 * k) - 1) * θ / 2))) + (2.5 * a), (f * cos((((2 * k) - 1) * θ / 2)))), (((-1 * f) * sin((((2 * k) - 1) * θ / 2))) - sin(((k - 1) * θ)) + (2.5 * a), (f * cos((((2 * k) - 1) * θ / 2))) + cos(((k - 1) * θ))), (((-1 * f) * sin((((2 * k) - 1) * θ / 2))) - sin(((k - 1) * θ) + θ / d) + (2.5 * a), (f * cos((((2 * k) - 1) * θ / 2))) + cos(((k - 1) * θ) + θ / d))], k, 1, c) → list7Sequence(Sequence[Sequence[Segment[(((-1 * f) * sin((((2 * k) - 1) * θ / 2))) + (2.5 * (m - 1)), (f * cos((((2 * k) - 1) * θ / 2)))), (((-1 * f) * sin((((2 * k) - 1) * θ / 2))) - sin(((k - 1) * θ) + (n * θ / d)) + (2.5 * (m - 1)), (f * cos((((2 * k) - 1) * θ / 2))) + cos(((k - 1) * θ) + (n * θ / d)))], n, 1, d - 1], k, 1, b], m, 1, a) → list8Sequence(Sequence[Segment[(((-1 * f) * sin((((2 * k) - 1) * θ / 2))) + (2.5 * a), (f * cos((((2 * k) - 1) * θ / 2)))), (((-1 * f) * sin((((2 * k) - 1) * θ / 2))) - sin(((k - 1) * θ) + (n * θ / d)) + (2.5 * a), (f * cos((((2 * k) - 1) * θ / 2))) + cos(((k - 1) * θ) + (n * θ / d)))], n, 1, d - 1], k, 1, c) → list9Polygon((0.016528925619834656, -3), (1.2165289256198346, -3), (1.2165289256198346, -1.3), (0.016528925619834656, -1.3)) → poly1, e, g, h, iGCD((a * b) + c - ((floor(((a * b) + c) / ((b * d))) * b) * d), (b * d)) → kSegment(A, P) → jSegment(C, R) → lSegment(B, Q) → mSegment(D, S) → n