Texas Instruments TI-84 Plus CE Getting Started page 44

Example:
To find the determinant of [C] as entered above:
▶
Use the ¾ MATH menu to paste the
- 1: det( command
-and-
¾ NAMES 3: [C]
-
as matrix variables to the Home Screen.
Remember that you cannot type in a matrix name from the calculator
Note:
keypad. Use the ¾ NAMES menu to paste a matrix name.
40 Working with Matrices