Mathematics: What is the sum of the geometric sequence −4, 24, −144, if there are 8 terms?

2/5 = 0.40.4 x 100 = 40%first u turn it into a decimal, then u multiply it by 100 to get ur percent...

What is the sum of the geometric sequence −4,

jmccrary2000

09.03.2022

The sum of 8 geometric sequence is 959780

Step-by-step explanation:

We are given

this sequence is geometric

-4 , 24 , -144

First term is -4

so, a_1=-4

now, we can find common ratio

$r=\frac{24}{-4}=-6$

we can use formula

$S_n=a_1(\frac{1-r^n}{1-r} )$

n=8

now, we can plug values

$S_8=-4(\frac{1-(-6)^{8}}{1+6} )$

now, we can simplify it

and we get

S_8=959780

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