Chapter 12 Sequences and Series - 12.3 Analyze Geometric Sequences and Series - 12.3 Exercises - Mixed Review - Page 817: 72

$210$

Here, we have $\sum_{i=2}^{8} 1+\sum_{i=2}^{8} i^2=8-1+\sum_{i=2}^{8} i^2$ $=7+\sum_{i=2}^{8} i^2$ Use a summation formula such as: $\sum_{i=2}^{8} i^2=\dfrac{n(n+1)(2n+1)}{6}$ Now, $7+\sum_{i=2}^{8} i^2=7+\dfrac{8(8+1)(2\times 8+1)}{6}=6+204=210$