Question

factor by grouping.
$3u^3 + 2u^2 + 21u + 14$

Explanation:

Step1: Group the terms

Group the first two terms and the last two terms: $(3u^3 + 2u^2) + (21u + 14)$

Step2: Factor out GCF from each group

Factor out $u^2$ from the first group and $7$ from the second group: $u^2(3u + 2) + 7(3u + 2)$

Step3: Factor out the common binomial

Factor out $(3u + 2)$ from both terms: $(3u + 2)(u^2 + 7)$

Answer:

$(3u + 2)(u^2 + 7)$