By default, the Formula Editor is not installed. If installed, insert -object, and then select Microsoft Formula 3.0.

If it is not installed, click Tools-Customize-Command, select Insert in the category box, then find the formula editor in the command box and drag it to the toolbar above. Then click this tool button and you will be asked whether to install it. Click Yes to start the installation. It should be noted here that when you first install OFFICE, if you don't delete the installation backup file, you will install it later. If you chose to delete the installation backup at that time, you must prepare the installation CD of OFFICE and put it in the CD-ROM drive.

You can then use the Formula Editor to edit the formula.