代数式是指用基本的运算符号（加、减、乘、除、乘法、开方）把数或表示数字的字母连起来的式子。代数式的分类：（在实数范围内）有理式、无理式，有理式包括整式和分式，整式包括单项式和多项式。 代数式就是用字母表示常数或变量的表达式，其中也可包含数字。代数式包括整式和分式。分别用以下方式表示：

In mathematics, an algebraic expression is an expression built up from integer constants, variables, and the algebraic operations (addition, subtraction, multiplication, division and exponentiation by an exponent that is a rational number). For example, is an algebraic expression. Since taking the square root is the same as raising to the power ,