Solution 34840: Specifying Infinity in a Calculation Using the TI-84 Plus C Silver Edition.
How do I specify infinity in a calculation using the TI-84 Plus C Silver Edition?The TI-84 Plus C Silver Edition does not include an infinity symbol. An alternate method for inputting values for either positive or negative infinity can be used.
Example - To specify positive infinity, input 1E99. To specify negative infinity, input -1E99.
The "E" symbol is short for scientific notation and can be accessed by pressing [2nd] [EE]. -1E99 can be interpreted as "negative one times 10 to the ninety-ninth power".
Please see the TI-84 Plus C Silver Edition guidebook for additional information.