Texas Instruments TI-89 사용자 설명서

3D Graphing

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For example, suppose you trace the paraboloid z(x,y) = x

2

+ .5y

2

 graphed with the 

indicated Window variables. You can easily move the cursor to a position such as:

Although the cursor is actually tracing the paraboloid, it appears off the curve because 
the trace coordinates:

•

 and 

 are within the viewing cube.

– but –

•

 is outside the viewing cube.

 QuickCenter lets you center the viewing cube on the cursor’s location. Simply 

press 

¸.

When 

 is outside the z boundary of the viewing cube, the cursor is physically displayed 

at 

 or 

 (although the screen shows the correct trace coordinates).

Rotating and/or Elevating the Viewing Angle

Rotating and/or Elevating the Viewing Angle

Rotating and/or Elevating the Viewing Angle

Rotating and/or Elevating the Viewing Angle

In 3D graphing mode, the 

q and 

f Window variables let you set viewing angles that 

determine your line of sight. The 

ψ

 Window variable lets you rotate the graph around 

that line of sight.

Trace cursor

Valid trace 
coordinates