Casio FX-991ES Scientific Calculator User Manual

About this manual

This manual introduces the FX-991ES calculator, covering safety precautions, battery handling, and basic operation procedures. It explains the notation used in the guide, how to set display and angle formats, and how to use the various memory functions.

Additional sections describe proper care of the device, including avoiding drops, twists, exposure to fire, and keeping it away from children. The manual also details the reset procedure to return the calculator to its initial state and provides troubleshooting tips for common issues. This manual is written in Japanese.

What's inside

• Introduction
• Notation
• Examples
• Safety Precautions
• Battery Information
• Display Settings
• Angle Settings
• Memory Usage
• Reset Procedure
• Warranty Information

Specifications

Frequently asked questions

What type of battery does the FX-991ES use and how often should it be replaced?

The FX-991ES uses an LR44 battery, and it should be replaced at least every three years.

What safety precautions should be observed when using the FX-991ES?

Do not drop or apply strong shock, avoid twisting or bending the device, keep it away from fire, and keep batteries out of reach of children.