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The following are the special symbols that GC 3.5 uses. These can't
be used as variables.
You can find them by searching for "reserved" in the Help.
I've also included a copy of the page from the Help, found by using
the command "Show package contents" after Control-clicking on of the
Graphing Calculator application.
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Special symbols
Greek letters and special symbols
Greek letters and special symbols
The calculator recognizes three Greek letters: π, θ, Φ. It also reserves several characters for special use.
| Symbol | How to type | Value |
|---|---|---|
| π | Option + P or pi |
3.14159… |
| θ | Option + T or theta |
theta (the angle of (x,y) from the x-axis) |
| Φ | Option + F or phi |
phi (the angle of (x,y,z) from the z-axis) |
| e | e | 2.78128… |
| i | i | .png) |
| n | n | slider value |
| r | r |
|
You can also insert these characters using the Keypad.
Graphing variables
The letters x, y, z, r, θ, Φ, t, u, v, and w are variables. They have special meaning in Graphing Calculator and cannot be used for anything else.
The variables you type in an equation determine the coordinate system and type of graph drawn.
| Variables | Meaning |
|---|---|
| x, y | Rectangular coordinates in 2D |
| r, θ | Polar coordinates |
| z | Complex number x+iy |
| x, y, z | Rectangular coordinates in 3D |
| r, θ, z | Cylindrical coordinates |
| r, θ, Φ | Spherical coordinates |
| x, y, u, v | Rectangular coordinates in 4D |
| w, z | Complex values x+iy and u+iv in a complex surface |
| t | Parameter in a parametric curve |
| u, v | Parameters in a parametric surface |
Coordinate systems
In two-dimensional graphs, the variables x and y correspond to the Cartesian (or rectangular) coordinate system.
In two-dimensional graphs, the variables r and θ correspond to the polar coordinate system.
In three-dimensional graphs, the variables x, y, and z correspond to the right-handed Cartesian (or rectangular) coordinate system.
In three-dimensional graphs, the variables r, θ, and z correspond to the cylindrical coordinate system.
In three-dimensional graphs, the variables r, θ, and Φ correspond to the spherical coordinate system.