Determinate the Riemann sum: SUM[ f(Xk)deltaXk ] where k=1 to n if f(x)=x^2-x-2 for x E [-2,2] and n=4. The partition is regular and we should use the left end point of the subintervals.

Now i got Deltaxk=1 ; Xk=k-3 ; f(Xk)= k^2 - 7k + 10 ; And the final result i have is 60 .

I want to know should i have the same result if i`m solving the definite integral Integral of: (x^2-x-2)dx where a=-2; b=2 ; as the riemann sum result , which doesnt happens.