First, choose the input method you use (such as pinyin input, five-stroke input, etc.). ) and then click the text area where you want to enter symbols. The cursor will appear in this position, and the language bar will appear in the lower left corner (or lower right corner) of the screen. If pinyin input is used, the five cells in the language bar are pinyin input method icon, standard input status, half-angle input, punctuation mark and soft keyboard in turn from left to right, and a menu will pop up. Left-click on one of the "mathematical symbols", and a keyboard marked with various mathematical symbols will appear at the other end of the screen. It is ok to find the key corresponding to the symbol contained in (mine is J key), click the key on the soft keyboard with the mouse, or hit the corresponding key on the computer keyboard, but it is only included in, not included in.