Locus of Centers of Two Circles Tangent Externally
Loading the math board and drawing, please wait…
This example demonstrates the locus of centers of two circles that are tangent externally. Key mathematical concepts include circle, geometry, and locus. It uses commands such as Intersect, Point, Circle, PointIn, Line, Midpoint, OrthogonalLine, Segment, Distance, and Circumference in GeoGebra. Suitable for students at middle school level and above for geometric construction.
GeoGebra Commands & Parameters
Intersect(xAxis, yAxis) → APoint(yAxis) → OCircle(O, r_1) → cPointIn(b) → CCircle(C, r_2) → dLine(O, C) → hIntersect(c, h) → D, EIntersect(d, h) → F, GMidpoint(E, F) → ICircle(I, F) → kMidpoint(O, C) → M_3OrthogonalLine(M_3, h) → pCircle(O, r_1 + Δr) → qCircle(C, r_2 + Δr) → rIntersect(r, q) → L_2, L_1, ,Segment(O, L_1) → iSegment(O, L_2) → jSegment(L_1, C) → lSegment(L_2, C) → mIntersect(d, l) → L,Intersect(d, m) → N,Intersect(c, i) → P,Intersect(c, j) → Q,Circle(L_1, P) → sCircle(L_2, Q) → tMidpoint(D, G) → MCircle(O, R) → gCircle(C, R + r_1 - r_2) → c_1Intersect(g, c_1) → M_1, M_2, ,Line(M_1, O) → f_1Intersect(c, q, 1) → HIntersect(c, q, 1) → SIntersect(c, q) → T, , ,Intersect(c, f_1) → U, VLine(M_1, C) → g_1Intersect(d, r, 1) → WIntersect(d, r) → Z, , ,Intersect(d, r, 1) → A_1Intersect(d, r, 1) → B_1Intersect(d, r, 1) → C_1Intersect(d, r, 1) → D_1Intersect(d, r, 1) → E_1Intersect(d, r, 1) → F_1Intersect(d, g_1) → G_1, H_1Circle(M_1, V) → d_1Circle(C, r_2) → e_1Line(M_2, O) → aLine(M_2, C) → i_1Intersect(c, a) → B, I_1Intersect(d, r, 1) → J_1Intersect(d, r, 1) → K_1Intersect(d, r, 1) → L_3Circle(M_2, I_1) → k_1Distance(M_1, H_1) → distanceM1H1Distance(M_1, V) → distanceM1VCircumference(c) → circumferencecPointIn(c) → PointcIntersect(c_1, h, 1) → N_1Circle(M, G) → p_1
AI Drawing Prompt Reference
Draw two externally tangent circles and find the locus of their centers. Start by plotting the intersection of the coordinate axes, then draw a circle with one center point. Next, draw another circle with a point on the first circle as the center. Connect the centers and find the intersection points. Draw a circle with one intersection point as the center. Then, find the midpoints of the circles and draw a perpendicular line from one midpoint. Finally, draw the intersections of the enlarged circles, connect the centers to the intersections, and complete all related constructions.
The prompt above was compiled from the original drawing commands and is for reference only.