Since there are only 4 terms in the sum, it's not too much work to expand it as

Alternatively, we can use the well-known formulas


These sums start at n = 0, so in our given sum we will keep track of the 0-th term separately:

as expected.
I believe the answer is
X = -5
3 ^ -4 = 9^-2
Hope this helps!
Answer: 2.6
Step-by-step explanation:
28-15=13
13/5=2.6
Good luck! :)
Answer:
1 2/3
Step-by-step explanation:
fraction calc :)
Answer:
jjjjjjjjjjjjjjjjjjjjjjjjj