How do you perform arithematic operations in dos?

In DOS, you can perform basic arithmetic operations using the built-in COPY command in combination with arithmetic expressions. However, DOS does not natively support direct arithmetic calculations like modern programming languages. Instead, you can use batch files with the SET /A command for simple arithmetic, such as addition, subtraction, multiplication, and division. For example, to add two numbers, you would use SET /A result=5+3 and then echo the result with ECHO %result%.