Integration is driving me nuts!!!

So the question is to do with Riemann sums.

Question: Use Riemann summs to find the **exact** value of the definite integral of

g(x) = 2 - (x^3)

on the interval [0,4]. The value found should not be the area under the graph on the interval. Why?

**Note: **You need to use equal subintervals and the sums will be slightly easier if you use the right hand endpoints.

Answer: I can do everything but (and this may sound silly) I dont know how to incorporate the consant '2' into the sums. Im thinking my answer should come to -56 right. But I keep gettin 64!

Can anyone fully show me how to do this?

Also Im guessing value found is not the area under the graph because its the *signed* area, its the area above the *x*-axis minus the area below the *x*-axis. Is this right?

P.S. Sorry about not showing any of my working. I'm tired and am going to go to sleep soon. Thanks in advance for your guys help.