Locus Tool

Given a point B that depends on another point A belonging to a geometric object (e.g. line, segment, circle), activate the tool then select point B and point A to generate the locus of point B when A moves along its constraint.

  • Type f(x) = x^2 – 2 x – 1 into the Input Bar and press the Enter key.

  • Place a point A on the x-axis (see Mode point.svg Point tool or Point command).

  • Create the point B = (x(A), f'(x(A))) that depends on point A.

  • Select the tool Mode locus.svg Locus and successively select point B and point A to create the locus.

  • Drag point A along the x-axis to see point B moving along its locus line.

Locus will be undefined if the dependent point has been defined using the Point Command with two parameters or the PathParameter Command.

  • See also Locus command.