Question

Write out all terms and compute the sums.

Answer 1

@amistre64 can u help?

Answer 2

you need to determine the f numbers that the E sums up

Answer 3

ok

Answer 4

lol, not f numbers, the 5 numbers ....

Answer 5

you might want to start by writing out the defining rule 5 times

Answer 6

okay got it

Answer 7

now for each time its written, let i =0,1,2,3,4 .... and compute the value of each term

Answer 8

sin(i pi) is always zero, so thats just thrown in there as a distractions

the question is really asking for the sum of 4i, i=0,1,2,3,4

Answer 9

okay

Answer 10

so 4 sigma sign with 4 on top of it i 2 = 4i i = 0 + 1 + 2 + 3 + 4 ?

Answer 11

so did i write it correctly?

Answer 12

almost:

4i , i=0 ... 0
4i , i=1 ... 4
4i , i=2 ... 8
4i , i=3 ... 12
4i , i=4 ... 16
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add em

Answer 13

okay i get 40

Answer 14

so how about the sigma part?