Chapter 2: Main Application 43
• The example calculations are all performed using the Decimal mode (see page 44).
Using the e Key
Use the e key to input exponential values. You can also input exponential values using the E key on the
soft keyboard [Number] key set.
0202 Calculation examples
Omitting the Multiplication Sign
You can omit the multiplication sign in any of the following cases.
• In front of a function… 2sin (30), 10log (1.2), etc.
• In front of a constant or variable… aπ, 2ab, 3ans, etc.
• In front of an open parenthesis… 3(5 + 6), (a + 1)(b – 1), etc.
Note that you must use a multiplication sign when the expression directly in front of the open parenthesis is a
literal variable. Example: ab (3 + b) must be written ab × (3 + b). Otherwise, your input is considered to be in
function notation (
f ( x )).
• In front of the e key or E key (See “Using the e Key” above.)
• In front of a matrix or list… a {1, 2, 3}, 3 [[1, 2] [3, 4]], etc.
Using the Answer Variable (ans)
Any time you execute a calculation in the Main application work area, the last result is assigned automatically
to a variable named “ans” (answer). You can even recall current “ans” variable contents and input them into
another calculation by tapping the D key on the soft keyboard.
0203 Calculation examples
Tip: Starting a calculation expression with +, −, ×, ÷, or ^ operator will cause the “ans” variable to be inserted automatically
to the left of the operator, even if you do not tap the D key.
Assigning a Value to a Variable
Besides using the variable assignment key (W, page 31), you can also use the syntax shown below in the Main
application and eActivity application to assign a value to a variable.
Syntax: Variable: = value
0204 Assign 123 to variable x
Important!
“:=” can be used only in Main and eActivity. It can NOT be used in a program. In the Program application, you
must use W to store a value to a variable.
