Find the sum.
$\sum _ { i = 1 } ^ { 4 } ( - i - 4 )$

Name: Find the sum. $\sum _ { i = 1 } ^ { 4 } ( - i - 4 )$
Brand: Quizplus
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Question

Quizplus · Accepted Answer

Using the formula for the sum of an arithmetic series, we have:

\begin{align*}
\sum_{i=1}^4 (-i-4) &= -\sum_{i=1}^4 (i+4) \
&= -\left[\frac{(1+4)+(2+4)+(3+4)+(4+4)}{2}ight] \
&= -\frac{28}{2} \
&= -14
\end{align*}

Therefore, the correct answer is choice C, which is the closest to -14.

Find the Sum ∑i=14(−i−4)\sum _ { i = 1 } ^ { 4 } ( - i - 4 )∑i=14​(−i−4)

Find the Sum $\sum _ { i = 1 } ^ { 4 } ( - i - 4 )$