An = a1 * r^(n-1)
-405 = -5*3^(n-1)
3^(n-1) = 81
3^4 = 81 so n-1 = 3 and n = 4
Sn = S4 = -5 (1 - 3^4) / ( 1 - 3) = 400 / -2 = -200 Answer
Given:
second term = 18
fifth term = 144
The nth term of a geometric sequence is:

Hence, we have:

Divide the expression for the fifth term by the expression for the second term:

Substituting the value of r into any of the expression:

Hence, the explicit rule for the sequence is:
Answer:
4x^4-2
Step-by-step explanation:

Hope this helps!
Answer:
89414,89416,89418
Step-by-step explanation:
Let n bet the positive integer and then 2n is an even integer because multiplying n with 2 makes it an even integer.
Now, 2n+2, 2n+4 are the next integers.
Therefore, three consecutive integers are: 2n, 2n+2, 2n+4.
It is given that twice the first integer added to the second is 268,244 that means:




Therefore, three consecutive integers are:
2n=89414, 2n+2=89416, 2n+4=89418