Find the sum of the even integers between
-50 and 200 including them, that is,
-50+(-48)+(-46)+....+198+200
Write down and use the correct formula.
Hello, Steph07!
Find the sum of the even integers between -50 and 200, inclusive.
That is: .$\displaystyle \text{-}50+(\text{-}48)+(\text{-}46)+ \hdots +198+200$
Write and use the correct formula.
This is an arithmetic series with:
. . first term $\displaystyle a = -50$, common difference $\displaystyle d = 2$, and $\displaystyle n=126$ terms.
The sum is: .$\displaystyle S \;=\;\tfrac{n}{2}[2a + (n-1)d] \;=\;\tfrac{126}{2}[2(-50) + 125(2)] \;=\;9450$