Question

PLEASE HELP ASAP!!! CORRECT ANSWER ONLY PLEASE!!!

What is [100(−4)^n-1} equal to?

Answer 1

Answer: -5100

Explanation:

`\sum^4_1[100(-4)^(n-1)]\qquad \rightarrow \qquad a_1=100\ \text{and r = -4}\\\\\\S_n=(a_1(1-r^n))/(1-r)\\\\\\\\S_4=(100(1-(-4)^4))/(1-(-4))\\\\\\.\quad=(100(1-256))/(1+4)\\\\\\.\quad=(100(-255))/(5)\\\\.\quad=20(-255)\\\\.\quad=-5100\\`