Hand Out for IC West High meeting 2:45 p.m.-4 p.m. Thursday April 24, 2003

QDAR2.gsp

Pick an independent variable, like length of ab or the perimeter.

To graph the area function, (independent variable, area) choose from the menu bar

Graph/CreateAxes.

Then highlight the measurement (first) independent variable by clicking on it with the cursor.

Now hold down the Shift key and highlight the area measurement.

Varying the independent variable makes the point (independent variable, area) trace along the graph. Use Display/TracePoint to see a trace.

What happens if you drag ab a lot?

QdAraFcnPrmSd.dpg

DPGraph view of the area as a function of length ab (x) and perimeter (y), with a = angle BAC

z = x * ( (1 / 2)*y –x ) * sin(a)

Use the keyboard ARROW KEYS

¬ ® ¯

to rotate this surface in three-space.

Use the keyboard PgDn to zoom out, PgUp to zoom in

To see slices of this surface, from the MENU BAR choose

SCROLLBAR

then click a VARIABLE

then click OK

Back in the graphic, move the scrollbar at the RIGHT SIDE of the window. What do the graphics mean in terms of the quadrilateral and its attributes?

Pick an independent variable, like length of ab or the perimeter.

To graph the angle BAC function, first measure it as follows:

Then highlight the measurement (first) independent variable by clicking on it with the cursor.

Hold down the Shift key and click on the vertices the angle B, then A then C

Choose from the menu bar

Measure/Angle.

Now repeat the previous process with for the pair (independent variable, angle BAC)

A DPGraph view of the angle BAC = z as a function of the area (a) and the side lengths x = ab and y = ac

z = ArcSin( a / ( x * y ) )

One more:

Same tasks as before:

rotate this in space, zoom in or out,

‘scrollbar’ some variables and interpret in terms of the angle function!