Rewrite the numerator as
x ² + 3x + 5 = (x - 1/2)² + 4 (x - 1/2) + 27/4
Then
(x ² + 3x + 5) / (2x - 1) = 1/2 × (x ² + 3x + 5) / (x - 1/2)
… = 1/2 × ((x - 1/2)² + 4 (x - 1/2) + 27/4) / (x - 1/2)
… = 1/2 × ((x - 1/2) + 4 + 27 / (4 (x - 1/2)))
… = 1/2 x + 7/4 + 27 / (8 (x - 1/2))
which clearly has a non-removable singularity at x = 1/2, which is to say this function has a domain including including all real numbers except 1/2.
For every number other than x = 1/2, the function takes on every possible real numbers, since 1/2 x + 7/4 alone takes on all real numbers.
So:
domain = {x ∈ ℝ | x ≠ 1/2}
range = {x ∈ ℝ}
