Answer :
Answer:
Step-by-step explanation:
1(8)^2-1
its the first variable then the the third one and u raise it by what the number is and u subtract by one
Answer:
1/2 n^2 + 3/2 n - 1.
Step-by-step explanation:
1 4 8 13 19 26
Differences 3 4 5 6 7
2nd Diff: 1 1 1 1
This means that a in the formula a^2n + bn + c = 1/2 ( as 2a = 1).
Now The first difference is 3 and we plug this into the formula:
3a - b = first difference
3(1/2) + b = 3
b = 3 - 3/2 = 3/2.
So we have the formula 1/2 n^2 + 3/2 n + c
So using the first term 1 : 1/2(1)^2 + 3/2 + c = 1
c = 1 - 3/2 - 1/2 = 1 -2 = -1.
Formula is therefore 1/2n^2 + 3/2 n - 1.