Question

Please help!! WILL MEDAL!!

What is the sum of the arithmetic series below? Use the formula for the sum of an arithmetic series.

Answer 1

18
Σ 2i + 8 = 10 + 12 + .....+ 44 = 486
i = 1

Answer 2

get the 1st and the last term!
to find 1st term = a1 , plug in i=1
in \(2i +8\)

to get the last term , 18th term, plug in
i=18 in \(2i+8\)

Answer 3

then find the sum using the formula
\(\Large S_n = (n/2)(a_1+a_n)\)

Answer 4

n= number of terms
a1 = 1st term
an = last term