Sample 3—Geometry example

The Geometry Xpander environment lets you mix analytic and geometric representations. Here, line AB has been constrained to pass through the origin with slope 1/2. The point C is constrained to lie on line AB. The x-coordinate of point D is constrained to be equal to the x-coordinate of point C, and the y-coordinate of point D is constrained by the value of the expression 0.5*(x-coordinate of C) * (y-coordinate of point C). The system has been set to leave a "trail" behind point D as point C is moved along the line. Cool, huh?

See pages 119-122 in the Math Xpander User's Guide for other point trail examples.