In Exercises 83–92, factor by introducing an appropriate substitution.3(x+1)² − 5(x+1) + 2 (Let u = x+1)

Factoring polynomials involves rewriting a polynomial expression as a product of simpler polynomials. This process is essential for simplifying expressions and solving equations. In the given question, recognizing the structure of the polynomial allows for easier manipulation and solution.

The substitution method is a technique used to simplify complex expressions by replacing a variable or expression with a single variable. In this case, letting u = x + 1 transforms the polynomial into a more manageable form, making it easier to factor and solve.

Quadratic expressions are polynomials of degree two, typically in the form ax² + bx + c. They can often be factored into the product of two binomials. Understanding the characteristics of quadratic expressions is crucial for applying factoring techniques effectively, as seen in the exercise.