Question 0502d

Sigma Notation

Bottom Limit Handling

Question

It is given that

{u_r = 2 r + 2}

and

\sum_{r=1}^n u_r = n^2 + 3 n - 4.

Find an expression for

\displaystyle \sum_{r=13}^{n} u_r.

in the form

{n^2 + Bn + C,}

where

{B}

and

{C}

are constants to be determined.

{B = }

{C = }