How to find the implied domain of a function

The video tutorial explains the concept of domain in mathematical expressions, focusing on the restrictions that arise when dividing by zero or taking the square root of a negative number. It provides a step-by-step guide on how to determine the domain by setting the denominator of a rational expression to zero and ensuring the expression under a square root is non-negative. The tutorial concludes with a discussion on the domain of expressions and addresses common questions.

What does it mean when we say that a number cannot be zero on the bottom of a rational expression?

How would you express the domain of a function that is greater than or equal to -5?