HP Prime Graphing Wireless Calculator - Manual (Page 58)

54 Geometry
Example:
rotate(GA, angle(GB, GC, GD),GK) rotates the
geometric object labeled K, about point A, through an angle
equal to ∡ CBD.
Dilation
Dilates a geometric object, with respect to a center point, by
a scale factor.
homothety(point, realk, object)
Example:
homothety(GA, 2, GB) creates a dilation centered at
point A that has a scale factor of 2. Each point P on geometric
object B has its image P’ on ray AP such that AP’=2AP.
Similarity
Dilates and rotates a geometric object about the same center
point.
similarity(point, realk, angle, object)
Example:
similarity(0, 3, angle(0,1,i),point(2,0))
dilates the point at (2,0) by a scale factor of 3 (a point at
(6,0)), then rotates the result 90° counterclockwise to create a
point at (0, 6).
Projection
Draws the orthogonal projection of a point onto a curve.
projection(curve, point)
Inversion
Draws the inversion of a point, with respect to another point,
by a scale factor.
inversion(point1, realk, point2)
Example:
inversion(GA, 3, GB) draws point C on line AB such
that AB*AC=3. In this case, point A is the center of the
inversion and the scale factor is 3. Point B is the point whose
inversion is created.