Answer
$=1760$
Work Step by Step
By using the binomial theorem, we can expand the algebraic expression in the form of:
$(ax+b)^n=\binom{n}{0}a^nb^0x^n+\binom{n}{1}a^{n-1}b^1x^{n-1}+...+\binom{n}{n-i}a^{i}b^{n-i}x^{i}+...+\binom{n}{n-1}a^1b^{n-1}x^1+\binom{n}{n}a^0b^nx^0$
There, we can see that the coefficient of $x^i$ is $\binom{n}{n-i}a^{i}b^{n-i}$.
In this case, $a=2$, $b=1$, $n=12$, $i=3$; therefore, the coefficient will be:
$\binom{12}{9}2^31^{12-3}=\binom{12}{9}2^31^9=220\times 8=1760$