Chapter 3 - Quadratic Functions - 3.1 Introduction to the Family of Quadratic Functions - Exercises and Problems for Section 3.1 - Skill Refresher - Page 120: S4

$(x+2)(x+1)$

To factor, find two numbers that can be multiplied to create $2$ and added to create $3$. In this case, the numbers are $2$ and $1$. Thus, the factorization is $(x+2)(x+1)$. Check by FOILing out the expression. $$(x+2)(x+1)=x^2+2x+x+2=x^2+3x+2$$