Question

Find the sum of the first 26 terms of the following sequence:

12, 18, 24 . . .

Answer 1

i got 2210 but idont know if its right or wrong

Answer 2

what did you get for common difference ?

Answer 3

12

Answer 4

actually -6

Answer 5

common difference = d = difference between consecutive terms

d= 18-12 = 24-18 = ... ?

Answer 6

not even -6

Answer 7

sorry got mixed up 6

Answer 8

now use the sum formula.
have it ?

Answer 9

n =26
a= 12
d=6

Answer 10

s26=26/2(2*2(26-1)6)
26/2(2*2(25)6)
26/2(2*12+(150)
26/2(24+(150)
26/2(174)
13(1740
2262

Answer 11

\(\huge \checkmark \)

Answer 12

thanx again :)

Answer 13

welcome ^_^