Question

idk how to simplify these kind of stuffs -.-💀

Answer 1

You can find the first term and see what the common difference is

Answer 2

2i - 12, replace i with its initial value of 7

Answer 3

2?

Answer 4

This will give you the first term of AP

Answer 5

what's AP

Answer 6

The common difference is d = -12

Answer 7

You essentially have an arithmetic sequence

Answer 8

Yeah no the common difference is 2

Answer 9

i did show you one like this a while ago did i not?

\[\sum_{n=7}^{16} 2i-12\]
10 different scenarios -- from 7 to 16:
\[ ( 2\times 7-12 ) + ( 2\times 8-12 ) + ( 2\times 9-12 ) + ( 2\times 10-12 ) + ( 2\times 11-12 ) + ( 2\times 12-12 ) + ( 2\times 13-12 ) + ( 2\times 14-12 ) \\ + ( 2\times 15-12 ) + ( 2\times 16-12 ) \]
yeah

Answer 10

but why is one i and one n

Answer 11

It's an arithmetic series starting at 7*2-12 = 2
and ending at 16*2-12 = 20
common difference is 2, so 2+4+6...+20
or 2(1+2+3...+10)
a lot easier now

Answer 12

110 💀💀💀

Answer 13

yes exactly

Answer 14

oh

Answer 15

Another way to solve is continue where we started.
a1 = 2, d = 2, n = 10, use the formula for the sum of the first n terms

Answer 16

.. of arithmetic progression

Answer 17

3 ways to do one thing 💀