As it is virtually impossible to list all the symbols ever used in mathematics only those symbols which occur often in mathematics or mathematics education are included. From geometry you know that Ar pr2 indicates the area of a circle given in terms of the value of the radius r while Cr 2pr indicates the circumference given in terms of the radius r. Without the parentheses it would not be clear that the first x belongs inside the numerator or that the 5x 6 belongs inside the denominator.
X 2 x 2 5 x 6.
While this is a serious limitation multi-level formulas are not always needed and even when they are needed proper math symbols still look better than improvised ASCII approximations. These mathematical operators and symbols range from simple addition and subtraction to more complicated operations like integration and the like. In mathematics an equation is a statement that asserts the equality of two expressions which are connected by the equals sign. For example 3 2.