## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

$(6a+7)(a^2+1)$
Using factoring by grouping, the factored form of the given expression, $6a^3+7a^2+6a+7 ,$ is \begin{array}{l} (6a^3+7a^2)+(6a+7) \\\\= a^2(6a+7)+(6a+7) \\\\= (6a+7)(a^2+1) .\end{array}