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2 years ago

The sum of the first 15 terms of a geometric sequence with 7 as the first term and a common ratio of -3 is __________.

Mathematics

1 answer:

Andre45 [30]2 years ago

4 0

Step-by-step explanation:

the formula for the sum of the first n terms of a geometric sequence is

Sn = s1(1 - r^n)/(1 - r)

with r being the common ratio and s1 is the first term.

so,

S15 = 7×(1 - (-3)¹⁵)/(1 - -3) = 7×(1 - -14,348,907)/4 =

= 7×14,348,908/4 = 7×3,587,227 = 25,110,589

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3 years ago

Find the midpoint of the segment with the following endpoints.<br> (-3,8) and (-8, 2)

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3 years ago

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$p=x^2+\dfrac{1}{x^2}\\\\p=\dfrac{x^4}{x^2}+\dfrac{1}{x^2}\\\\p=\dfrac{x^4+1}{x^2}\qquad(*)$

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3 years ago

24= g/g +20. g/g is a fraction.

Stells [14]

Answer:

Subtract 20 from both sides.

24−20=9/g

2 Simplify 24-20 to 4

4=9/g

3 Multiply both sides by 9

4×9=g

4 Simplify 4×9 to 36

36=g

5 Switch sides.

g=36

Step-by-step explanation:hope it helps plz Mark me brainliest

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3 years ago