Symbolic Manipulation
234
Determining If a Variable Is Exists
Determining If a Variable Is Exists
Determining If a Variable Is Exists
Determining If a Variable Is Exists
•
If
x
is defined, the result may be in a form
you did not expect.
Note:
When defining a variable, it’s a good
practice to use more than one character
in the name. Leave one-character names
undefined for symbolic calculations.
Method:
Example:
Enter the variable name.
Use the
isVar()
function.
Unless you knew that
5 had been stored to
x previously, the
answer 75 could be
misleading.
If defined, the variable’s
value is displayed.
If undefined, the variable
name is displayed.
If defined, “true” is
displayed.
If undefined, “false” is
displayed.
Summary of Contents for Voyage 200
Page 36: ...Getting Started 36 D B D B Press Result ...
Page 45: ...Getting Started 45 3 0 D B D D B D Press Result ...
Page 46: ...Getting Started 46 D 2 0 0 2 D B Scroll down to October and press Press Result ...
Page 60: ...Getting Started 60 B D Press Result ...
Page 139: ...Previews 139 8 Complete the operation Press 2 d Steps and keystrokes Display 5 f 2 ...
Page 453: ...Differential Equation Graphing 453 ...
Page 468: ...Tables 468 ...
Page 777: ...Activities 777 ...