等腰直角三角形(45-45-90)
几何画板及绘图内容加载中,请稍等……
①本范例通过动态演示等腰直角三角形的性质,帮助学生直观理解其特点;②涉及核心数学概念包括等腰三角形、直角三角形、对称性、三角函数等;③作图要点运用了Circle(圆)、Segment(线段)、OrthogonalLine(垂线)、Rotate(旋转)、Angle(角度)、Ray(射线)、Intersect(交点)、Polygon(多边形)、Line(直线)、Point(点)、Dilate(缩放)、CircleSector(扇形)、Vector(向量)、Translate(平移)等GeoGebra命令和对象;④适合高中数学教学,用于几何作图与性质探究。
GeoGebra 命令及参数
Circle(B, C) → cSegment(B, C) → aOrthogonalLine(C, a) → bRotate(C, 45°, B) → C'Angle(C, B, C') → αRay(B, C') → dIntersect(b, d) → ASegment(A, C) → eSegment(B, A) → fPolygon(B, C, A) → poly1, a_1, b_1, c_1Line(B, C) → hPoint(h) → DPoint(h) → ERay(C, E) → iPoint(i) → FRay(C, F) → jDilate(B, If[0 < g ≤ 1, 1 - g, 0], C) → B'Segment(B, B') → kDilate(C, If[1 < g ≤ 2, 2 - g, 0], A) → C'_1Segment(C, C'_1) → lCircle(C, (0.15 * a)) → pIntersect(p, j, 1) → GIntersect(p, e, 1) → HIntersect(p, a, 1) → ICircle(A, (0.15 * a)) → qCircle(B, (0.15 * a)) → rIntersect(q, e, 1) → JIntersect(q, f, 1) → KCircleSector(C, H, I) → sDilate(A, If[2 < g ≤ 3, 3 - g, 0], B) → A'Segment(A, A') → mCircleSector(A, K, J) → tRotate(s, If[3.5 < g ≤ 4.5, ((-(g - 3.5)) * π / 2), -1.5707963267948966], C) → s'Dilate(A, If[5.5 < g ≤ 6.5, 6.5 - g, 0], B) → A'_1Vector(A, A'_1) → uTranslate(t, u) → t'Rotate(B, If[4.5 < g ≤ 5.5, ((-(g - 4.5)) * π / 2), -1.5707963267948966], C) → B'_1Rotate(B', If[4.5 < g ≤ 5.5, ((-(g - 4.5)) * π / 2), -1.5707963267948966], C) → B''Segment(B'_1, B'') → k'Rotate(t', If[6.5 < g ≤ 7.5, (((-(g - 6.5)) * 5) * π / 4), -3.92699], B) → t''Dilate(A, If[7.5 < g ≤ 8.5, 8.5 - g, 0], C) → A'_2Vector(A, A'_2) → vTranslate(t, v) → t'_1Rotate(t'_1, If[8.5 < g ≤ 9.5, (((-(g - 8.5)) * 3) * π / 4), -2.356194490192345], C) → d_1Dilate(A, If[9.5 < g ≤ 10.5, 10.5 - g, 0], C) → A'_3Vector(A, A'_3) → wTranslate(t, w) → t'_2Rotate(t'_2, If[10.5 < g ≤ 11.5, ((-(g - 10.5)) * π / 2), -1.5707963267948966], C) → e_1