Question

evaluate: $sum_{k=2}^{5}(4k - 2)$
select one:
a. 48
b. 24
c. 122
d. 50

Explanation:

Step1: Expand the summation

Substitute $k=2,3,4,5$ into $4k-2$:
When $k=2$: $4(2)-2=6$
When $k=3$: $4(3)-2=10$
When $k=4$: $4(4)-2=14$
When $k=5$: $4(5)-2=18$
So the sum is $6+10+14+18$

Step2: Calculate the total sum

$6+10=16$, $14+18=32$, then $16+32=48$

Answer:

A. 48