Determine the constraints and add two rational expressions

The video tutorial explains the process of determining the least common denominator (LCD) when expressions have no common elements. It involves multiplying the expressions, using the FOIL method for distribution, and combining like terms to simplify the result. The instructor emphasizes understanding constraints and leaves the final answer in factored form for clarity.

Describe the importance of simplifying the numerator in polynomial expressions.

What constraints must be understood when solving the equation involving the expressions given?