^{5}+4x

^{3}+ x

^{2}+ 2x + 5 is also a expression. Now we come across a very common question what is a Mathematical Expression.

So we can say that a mathematical expression is defined as an expression which includes mathematical terms. It is formed by the combination of Numbers, variables and mathematical operations or mathematical terms. Mathematical expression are divided into three categories first is linear expressions which is defined as an expression consisting of simple terms or we can say linear terms. Second category is Quadratic expression which is defined as an expression which involves Square terms in the expression. Third type of mathematical expression is rational expression which is defined as the mathematical expression involving two expressions in a rational form.

A mathematical expression may be of one of these types. Constants are defined as the terms which cannot be changed and are stable or we can say there values are same for all the expressions. Variables are defined as the terms which are not constant for any particular expression. Its value may vary and can be changed. It does not have any constant value. A mathematical expression involves all types of mathematical operations over it that is addition, subtraction, multiplication, division, squaring, square root and many more other mathematical operations. Suppose an expression x

^{2}+ 2x + 5. Here, 'x' is a variable, 2 is coefficient of 'x' and 5 is a constant. And the 2 in x

^{2}is power or we can say it is an exponent in this expression.