Question

Find the arc length of the graph, on the interval [1/2,2] of y=(x^3/6)+(1/2x)

Answer 1

$$\large\mathbf \int^2_\frac{1}{2}\sqrt{1+ (\frac{dy}{dx}})^2 dx$$

Answer 2

So which is that?
33/16
18/5
47/24
39/14