## Intermediate Algebra (12th Edition)

$x^{2}+2x+1$
From Page 302, we know that the square of a binomial sum $x+y$ is given by the following equation: $(x+y)^{2}=x^{2}+2xy+y^{2}$ Therefore, $(x+1)^{2}=x^{2}+2(x)(1)+1^{2}=x^{2}+2x+1$.