1. First, open the document where the formula needs to be inserted, and determine the location of the formula.
2. Click "Mathematical Type" 2. Click Display 3 to open the formula input dialog box.
3. Enter the formula.
4. Enter all the formulas.
5. Put the mouse behind the formula, and then click Insert Number.
6. Place the mouse between the formula and the number, and then press the Tab key.
7. Serial number succeeded, and it appeared (1. 1).
8. According to this method, complete all the numbers (1. 1)(2. 1).