Question

What is the sum of the series below?

Answer 1

\[\sum_{i=1}^{6}(8i-2)\]

Answer 2

there are few enough terms here so you can just add

Answer 3

Use the formula: xn = a + d(n-1)

Answer 4

Where a is the first term and d is the common difference

Answer 5

n=number of terms

Answer 6

replace \(i\) by 1, 2, 3, 4, 5, 6 and put plus signs between them
\[8-2+8\times 2-2+8\times 3-2+8\times 4-2+8\times 5-2+8\times 6-2\]

Answer 7

or if you want to be fancy
\[8(1+2+3+4+5+6)-2\times 6\]

Answer 8

or if you want to be real fancy, what @Luigi0210 said

Answer 9

Haha, what i did was not fancy at all.

Answer 10

thanks guys!

Answer 11

yw

Answer 12

156

Answer 13

@satellite73