Fractional discriminant Generally, if a and B represent two integers and B contains letters, then the algebraic expression a / B is called a fraction Why is B / 2 π not a fraction? Because Pi is a mathematical symbol, isn't it a letter?

Fractional discriminant Generally, if a and B represent two integers and B contains letters, then the algebraic expression a / B is called a fraction Why is B / 2 π not a fraction? Because Pi is a mathematical symbol, isn't it a letter?

The letters here refer to "unknowns" and independent variables, not all the letters in the formula. Some letters in the formula do not represent variables, such as the well-known linear equation,
Y = ax + B, where a and B are not variables, so they are not "letters" as you say. As for π, it is a well-known constant. Of course, it is not a variable, and it does not belong to "letters" as you say