Take WORD as an example, it has its own formula editor, or it can download a third-party formula editor from the Internet.

Taking WORD2007 as an example, the method of calling the formula editor is as follows:

1. Open the Word document and click Insert → Text → Object.

2. Drag the slider in the "Object" column to find "Microsoft Formula 3.0" and press "OK".

3. At this time, the formula editor will pop up for the user to fill in the formula.