One thing I learned this week in Pre Calc 11 is how to determine non-permissible values for rational expressions. A rational expression is an algebraic expression that can be written as the quotient of two polynomials. A rational expression cannot contain roots of variables, or variables as exponents. Here are some examples of rational expressions, and expressions that are not rational expressions…

Rational expressions cannot have a denominator of 0. Therefore the variable in the denominator can not make the denominator equal to 0. The values for the variable that make the variable equal to zero are called non-permissible values. Follow the steps below I took to find the non-permissible value…