In the expansion of $\left(1+\dfrac{2}{x}\right)^8$, the coefficient of $\dfrac{1}{x^3}$ is —

Question

Accepted Answer

$448$

Answer

$112$

Answer

$224$

Answer

$336$

In the expansion of (1+2x)8\left(1+\dfrac{2}{x}\right)^8(1+x2​)8, the coefficient of 1x3\dfrac{1}{x^3}x31​ is —