I am clueless,
Find ∑(5 – 2 k ) when k goes from 2 to 7.
-24
24
30
-18
impatient much?
To find the sum ∑(5 – 2k) when k goes from 2 to 7, we can use the formula for the sum of an arithmetic series:
S = (n/2) * (first term + last term)
In this case, the first term is 5 – 2(2) = 5 – 4 = 1, and the last term is 5 – 2(7) = 5 – 14 = -9.
Now we need to find the number of terms (n). Since k goes from 2 to 7, there are 6 terms (including both 2 and 7).
Plugging the values into the formula:
S = (6/2) * (1 + (-9))
S = 3 * (-8)
S = -24
Therefore, the sum ∑(5 – 2k) when k goes from 2 to 7 is -24.