Question

When finding the sum of the arithmetic sequence 4 + 1 + -2 + -5 + -8 + -11, you will have a step of work that contains the number -3. Use complete sentences to describe how the -3 was calculated and what it means. WILL FAN AND GIVE MEDAL

Answer 1

PLS HELP.

Answer 2

-3 is the common difference, but I just need help explaining the formula of finding that out.

Answer 3

given sequence = 4 + 1 +(-2) + (-5) +(-8) +(-11)
thus this means
a0 = 4
a1 = 1
a2 = -2
and so on
as it is given in question that this series is an arithmetic series
thus
a1 = a0+d
1 = 4 + d
=> d = -3
a2 = a0+ 2d
-2 = 4 + 2d
-6 = 2d
-3 = d

now use the formula of ap series sum and find the sum

Answer 4

Thank you so much! :)