trumpetmaster7777
Given the sequence –3, 0, 3, which of the following is equivalent to:



This Question is Closed

trumpetmaster7777
Best Response
You've already chosen the best response.
0
\[\sum_{n=5}^{8}A subscript N\]

trumpetmaster7777
Best Response
You've already chosen the best response.
0
54
102
144
162

trumpetmaster7777
Best Response
You've already chosen the best response.
0
@primeralph @terenzreignz


RolyPoly
Best Response
You've already chosen the best response.
1
First term is 3, common difference is 0(3) = 3
So, the sequence is \[a_n = 3+3(n1)\]

trumpetmaster7777
Best Response
You've already chosen the best response.
0
so, we can do that plugging n2, n3 etc. into the next equations?

trumpetmaster7777
Best Response
You've already chosen the best response.
0
[3+3(n1)]+[3+3(n2)] etc.?

RolyPoly
Best Response
You've already chosen the best response.
1
You need to find sum from the fifth term to the eighth term, so, find a5, a6, a7, a8 and add them together.

RolyPoly
Best Response
You've already chosen the best response.
1
n is the number of term

trumpetmaster7777
Best Response
You've already chosen the best response.
0
that's right we start on 5 right? so like this?

RolyPoly
Best Response
You've already chosen the best response.
1
e.g.
\[a_5 = 3+3(51)=...\]

RolyPoly
Best Response
You've already chosen the best response.
1
Start from 5, yes.

trumpetmaster7777
Best Response
You've already chosen the best response.
0
[3+3(n5)]+[3+3(n6)]+[3+3(n7)]+[3+3(n8)]?

trumpetmaster7777
Best Response
You've already chosen the best response.
0
(3+3n15)+(3+3n18)+ (3+3n21)+ (3+3n24)?

trumpetmaster7777
Best Response
You've already chosen the best response.
0
am I doing this right?

trumpetmaster7777
Best Response
You've already chosen the best response.
0
(3n18)+(3n21)+(3n24)+(3nx)+(3n27)

trumpetmaster7777
Best Response
You've already chosen the best response.
0
i'm not sure what to do from there

RolyPoly
Best Response
You've already chosen the best response.
1
No

RolyPoly
Best Response
You've already chosen the best response.
1
\[a_5 = 3+3(51)\]\[a_6 = 3+3(61)\]\[a_7 = 3+3(71)\]...
Then, find \(a_5+a_6+a_7+a_8\)

trumpetmaster7777
Best Response
You've already chosen the best response.
0
=−3+3(5−1)
=−3+3(6−1)
=−3+3(7−1)
=3+3(81)

trumpetmaster7777
Best Response
You've already chosen the best response.
0
=6+15 =6+18 =6+21 =6+24
=9 =12 =15 =18
9+12+15+18


trumpetmaster7777
Best Response
You've already chosen the best response.
0
thank you so much guys