The Geometer’s Sketchpad
®
for TI-89, TI-92 Plus, and
© 2000-2002 KCP Technologies, Inc.
39
Voyage™ 200 PLT User Guide and Reference Manual
Commands
3
This chapter explains how to use the commands in Sketchpad’s six
menus:
ƒ
Edit,
„
Display,
…
Construct,
†
Transform,
‡
Measure, and
ˆ
Graph. The first section offers general
information about using menus. Other sections describe specifically
how to use the commands in each menu.
A sine wave emerging from a Sketchpad animation. This sketch
began with a horizontal segment and a circle centered at its left
endpoint. Points A and B were constructed on the circle and
segment, respectively. A horizontal line through A intersects a
vertical line through B at point C. When A and B are animated
at the same speed, C travels along the sine wave. The shaded
image is the trace of segment BC as both points animate
slowly. How long would the original horizontal segment have to
be in order for the sine curve to trace exactly one wave period?
A fishy tessellation. Periodic tessellations
are geometric patterns that, when
repeated, fill the plane. A starting rectangle
was used to construct an irregular polygon
whose vertices included the rectangle’s
corners. This polygon—or tile—was then
translated by vectors from each of the
rectangle’s corners to the corner diagonally
opposite, resulting in four new images of
the tile. These translations were repeated
as necessary to fill the screen, with white
spaces left over forming “opposite” tiles.
Dragging the vertices of the original tile
produces other related tessellations.