Answer
$12a^{17}$
Work Step by Step
$a\times4a^{11}\times3a^5=(1\times4\times3)(a^1\times a^{11}\times a^5)=12a^{1+11+5}=12a^{17}$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.