Set the denominator in equal to to find where the expression is undefined.

Factor using the perfect square rule.

Rewrite as .

Check the middle term by multiplying and compare this result with the middle term in the original expression.

Simplify.

Factor using the perfect square trinomial rule , where and .

Set the equal to .

Add to both sides of the equation.

The equation is undefined where the denominator equals , the argument of a square root is less than , or the argument of a logarithm is less than or equal to .

Find Where Undefined/Discontinuous (3x-18)/(x^2-12x+36)