Evaluate the sum.
-$$\sum _ { \mathrm { k } = 1 } ^ { 4 } ( - 1 ) ^ { \mathrm { k } } ( \mathrm { k } + 3 )$$
A) 22
B) 14
C) 2
D) $- 22$

Question

Quizplus · Accepted Answer

The sum can be calculated by substituting the values of $k$ from 1 to 4 into the given expression and adding them together. For $k=1$, the term is $(-1)^1(1+3) = -4$. For $k=2$, the term is $(-1)^2(2+3) = 5$. For $k=3$, the term is $(-1)^3(3+3) = -6$. For $k=4$, the term is $(-1)^4(4+3) = 7$. Adding these together, $-4 + 5 - 6 + 7 = 2$.

Evaluate the Sum ∑k=14(−1)k(k+3)\sum _ { \mathrm { k } = 1 } ^ { 4 } ( - 1 ) ^ { \mathrm { k } } ( \mathrm { k } + 3 )k=1∑4​(−1)k(k+3)

Evaluate the Sum $\sum _ { \mathrm { k } = 1 } ^ { 4 } ( - 1 ) ^ { \mathrm { k } } ( \mathrm { k } + 3 )$