It depends on your personal subjects and elective courses. If it involves advanced mathematics, engineering study and other subjects, it is recommended to equip a calculator. For example, Casio fx-99 1CNX has 498 calculation functions, including calculation modes, complex number, radix, matrix, vector, statistics, table, equation/function, inequality, proportion, etc. Basically, all high number problems can be solved. It is more intuitive to input and output mathematical formulas and their results in the form of teaching material display, and the display input is not wrong and the calculation is more accurate. It also has innovative functions such as Chinese display, high-definition LCD screen and dual power supply. More convenient operation, high-end durability, fashion and environmental protection.