To input and display plural numerical formulas in the same screen in a textbook format and also to input and display plural numerical formulas in a textbook format or a one-line format.

Plural formulas which are inputted in a textbook format or one-line format with a keyboard 2 are stored in a buffer for such format storage on data storage RAM memory 4. Plural stored formulas are expanded in a main buffer and a sub-buffer for a buffer for display and generation on the memory 4, and an image that synthesizes the two display and generation buffers is generated in VRAM on the memory 4 by using CG(character generator) data on program ROM 3, and is shown on a liquid crystal display 6 through a liquid crystal driver 5. This apparatus has a system which performs these processings by making a CPU 1 operate according to a program on the ROM 3.