Explore Properties of Tangents to a Circle
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This applet helps students discover the properties of tangents drawn to a circle from a point outside the circle. Key mathematical concepts include the properties of tangents to a circle. The construction uses GeoGebra commands such as Circle, Tangent, Intersect, etc. Suitable for students in middle school and above for geometric construction and circle properties.
GeoGebra Commands & Parameters
Circle(O, B_1) → cSegment(O, B_1) → aPointIn(b) → ETangent(E, c) → d, eIntersect(c, e, 1) → BIntersect(c, d, 1) → ARay(E, A) → fRay(E, B) → gSegment(O, A) → hSegment(O, B) → iDilate(O, If[0 < j ≤ 1, 1 - j, 0], A) → A'Dilate(O, If[0 < j ≤ 1, 1 - j, 0], B) → A'_1Segment(O, A') → kSegment(O, A'_1) → lAngle(E, B, O) → αAngle(O, A, E) → βCircle(A, (0.25 * a)) → pCircle(B, (0.25 * a)) → qIntersect(p, h, 1) → FIntersect(q, i, 1) → GIntersect(p, f) → H, IIntersect(q, g) → J, KCircle(O, B_1) → tDilate(O, If[1.3 < j ≤ 2.3, 2.3 - j, 0], E) → C'Polygon(B, E, O) → poly1, a_1, d_1, c_1Angle(A, E, B) → γRotate(B, If[5 < j ≤ 6, ((j - 5) * ((2 * π) - γ)), (2 * π) - γ], E) → D'_1Rotate(E, If[5 < j ≤ 6, ((j - 5) * ((2 * π) - γ)), (2 * π) - γ], E) → C'_1Segment(E, A) → nSegment(E, B) → b_1Polygon(O, E, A) → poly2, e_1, a_2, c_2Segment(O, C') → f_1Rotate(E, If[5 < j ≤ 6, ((j - 5) * (-γ)), (-γ)], E) → C'_2Rotate(B, If[2.5 < j ≤ 3.5, ((j - 2.5) * (-γ)), (-γ)], E) → D'Segment(C'_2, D') → h_1
AI Drawing Prompt Reference
Draw a circle with center O and a point B₁ on it, connecting O to B₁ as a radius. Place a point E outside the circle, and draw two tangents from E to the circle, touching at points A and B. Connect E to A and B, and also connect O to A and B. On segments OA and OB, place points A' and B' such that their distances from O are scaled by a factor. Display the angles AEB, EBO, and OAE. Draw small circles centered at A and B, intersecting the segments and tangents, and mark the intersection points. Construct triangles OBE and OEA, and include a rotating angle to dynamically explore the tangent properties.
The prompt above was compiled from the original drawing commands and is for reference only.