动态圆内切线与外切线角度关系演示
几何画板及绘图内容加载中,请稍等……
①本范例动态演示了在圆内切线与外切线情境下,两个角之间的变化关系;②涉及核心数学概念包括圆、切线、角、向量、几何变换等;③通过 GeoGebra 命令如 Circle, Segment, PointIn, Distance, Tangent, Intersect, Dilate, Angle, Line, Rotate 等实现图形构建与动态调整;④适合高中及以上数学学习者,用于理解几何关系与动态几何作图。
GeoGebra 命令及参数
Circle(A, B) → cSegment(A, B) → fPointIn(a) → CDistance(C, c) → bCircle(C, d) → eTangent(c, e) → g, h, i, jIntersect(c, h) → DIntersect(c, j) → E, NIntersect(e, j) → FIntersect(e, h) → G, LIntersect(e, g) → H, KIntersect(e, i) → IIntersect(c, i) → J, MIntersect(c, g) → OCircle(D, 2) → pCircle(E, 2) → qCircle(O, 2) → rCircle(K, 2) → sCircle(I, 2) → tCircle(F, 2) → c_1Circle(G, 2) → d_1Circle(J, 2) → e_1Intersect(e_1, i, 1) → PIntersect(e_1, i, 2) → QIntersect(p, h, 1) → RIntersect(p, h, 2) → SIntersect(c_1, j, 2) → TIntersect(c_1, j, 1) → UIntersect(d_1, h, 1) → VIntersect(d_1, h, 2) → WIntersect(s, g, 2) → ZIntersect(s, g, 1) → A_1Intersect(r, g, 2) → B_1Intersect(r, g, 1) → C_1Intersect(q, j, 2) → D_1Intersect(q, j, 1) → E_1Dilate(A, If[0 < k ≤ 1, 1 - k, 0], D) → A'Dilate(A, If[0 < k ≤ 1, 1 - k, 0], M) → A'_1Dilate(A, If[0 < k ≤ 1, 1 - k, 0], E) → A'_2Dilate(A, If[0 < k ≤ 1, 1 - k, 0], O) → A'_3Angle(A, O, C_1) → αAngle(A, E, E_1) → βAngle(A, D, S) → δIntersect(t, i, 1) → F_1Angle(C, I, F_1) → ζAngle(C, G, W) → θ_1Dilate(C, If[0 < k ≤ 1, 1 - k, 0], G) → C'Dilate(C, If[0 < k ≤ 1, 1 - k, 0], F) → C'_1Dilate(C, If[0 < k ≤ 1, 1 - k, 0], I) → C'_2Dilate(C, If[0 < k ≤ 1, 1 - k, 0], K) → C'_3Intersect(i, j) → G_1Intersect(i, j) → H_1Line(C, H) → k_1Line(O, E) → l_1Intersect(e, ee) → J_1, , ,Intersect(e, l_1) → K_1, L_1Segment(H, K_1) → lSegment(C, L_1) → mMin(m, l) → nCircle(H, (0.3 * n)) → f_1Segment(C, F) → g_1Intersect(f_1, g) → I_1, M_1Intersect(f_1, l) → N_1,Line(F, C) → i_1Intersect(e, i_1) → O_1, P_1Angle(N_1, H, I_1) → εRotate(P_1, ε, C) → Q_1Angle(P_1, C, Q_1) → γDilate(F, If[0 < k ≤ 1, 1 - k, 0], C) → F'Segment(F, F') → h_1Dilate(C, If[1 < k ≤ 2, 2 - k, 0], P_1) → C'_4Segment(C, C'_4) → j_1Dilate(O, If[2 < k ≤ 3, 3 - k, 0], E) → O'Segment(O, O') → m_1Dilate(E, If[3 < k ≤ 4, 4 - k, 0], K_1) → E'Segment(E, E') → n_1Dilate(K_1, If[4 < k ≤ 5, 5 - k, 0], L_1) → R_1Segment(K_1, R_1) → p_1Dilate(H, If[5 < k ≤ 6, 6 - k, 0], K_1) → H'Segment(H, H') → q_1Line(O, K_1) → s_1Angle(P_1, C, L_1) → ηRotate(I_1, If[6 < k ≤ 7, ((-(k - 6)) * ε), (-ε)], H) → S_1CircleSector(H, S_1, I_1) → r_1Dilate(C, If[7 < k ≤ 8, 8 - k, 0], L_1) → C'_5Segment(C, C'_5) → t_1Dilate(H, If[8 < k ≤ 9, 9 - k, 0], C) → H'_1Vector(H, H'_1) → wTranslate(r_1, w) → c_2Line(H, j_1) → a_1Line(H, t_1) → b_1Point(b_1) → T_1Angle(I_1, H, T_1) → θRotate(c_2, If[9 < k ≤ 10, ((k - 9) * θ), θ], C) → d_2Dilate(C, If[10 < k ≤ 11, 11 - k, 0], Q_1) → C'_6Segment(C, C'_6) → f_2Dilate(H, If[11 < k ≤ 12, 12 - k, 0], C) → H'_2Vector(H, H'_2) → u_1Translate(r_1, u_1) → e_2Rotate(e_2, If[12 < k ≤ 13, ((k - 12) * (θ - ε)), θ - ε], C) → g_2Segment(A, B) → h_2