1.11: Past-paper question 1

4PM1/1/June/2023 — Question 1 · 5 marks

(a) Show that r=1n(3r+2)=n2(3n+7)\quad (a) \text{ Show that } \sum_{r=1}^n (3r + 2) = \frac{n}{2}(3n + 7)
(3)
(b) Hence, or otherwise, evaluate r=1040(3r+2)(b) \text{ Hence, or otherwise, evaluate } \sum_{r=10}^{40} (3r + 2)
(2)