2 years ago

What is the sum of the geometric sequence -3, 18, -108, ... if there are 8 terms

Mathematics

1 answer:

creativ13 [48]2 years ago

6 0

Answer:

Step-by-step explanation:

common ratio=18/-3=-108/18=-6, a=-3

sn=a(r^n-1)(r-1)

sn=-3((-6)^n-1)(-6-1)

sn=-3(-6)^8-1)/(-7)

s8=-3(1679615)/(-7)

s8=719836

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$\bf \qquad \qquad \textit{inverse proportional variation}
\\\\
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\end{array}\\\\
-------------------------------$

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3 years ago

7 copies of the sum of 8 fifths and 4

Serggg [28]

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