Answer
$x^3+\dfrac{3}{4}x^2+\dfrac{1}{4}x+\dfrac{5}{8}+\dfrac{5}{8(2x-1)}$
Work Step by Step
Using the long division below, then
\begin{array}{l}\require{cancel}\left(
2x^4+\dfrac{1}{2}x^3-\dfrac{1}{4}x^2+x
\right)\div(
2x+1
)\\\\=
x^3+\dfrac{3}{4}x^2+\dfrac{1}{4}x+\dfrac{5}{8}+\dfrac{5}{8(2x-1)}
.\end{array}