"Insert"-"Special Symbol"-"Mathematical Symbol", the last one in the first line.

Second, how to add and subtract passwords?

To enter this symbol:

1, put a minus sign in the Word document. 2. Select the minus sign.

3. Select Chinese Layout from the Format menu.

4. "Circled Characters" in the submenu.

5. Select and confirm.

6. The symbol is typed:

Third, how to lose when the plus and minus signs go up and down?

Enter Chinese Pinyin Jia Jian and it will come out. Just click select.