# Algebraic fraction

A *complex fraction* is a fraction whose numerator or denominator, or both, contains a fraction. A *simple fraction* contains no fraction either in its numerator or its denominator. A fraction is in *lowest terms* if the only factor common to the numerator and the denominator is 1.

An expression which is not in fractional form is an *integral expression*. An integral expression can always be written in fractional form by giving it the denominator 1. A *mixed expression* is the algebraic sum of one or more integral expressions and one or more fractional terms.

where the second term is a proper rational fraction. The sum of two proper rational fractions is a proper rational fraction as well. The reverse process of expressing a proper rational fraction as the sum of two or more fractions is called resolving it into partial fractions. For example,

An *irrational fraction* is one that contains the variable under a fractional exponent.^{[4]} An example of an irrational fraction is