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3 years ago

What is the sum of the geometric sequence -4,24,-144, ... if there are 7 terms?

1 answer:

const2013 [10]3 years ago

4 0

$S_7=-4+24-144+864-5184+31104-186624$
$S_7=-4(1-6+36-216+1296-7776+46656)$
$(-6)S_7=-4(-6+36-216+1296-7776+46656-279936)$
$S_7-(-6)S_7=-4(1+279936)$
$S_7=-\dfrac47\times279937=-159964$

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Katarina [22]

Answer:

y = -8x+2020

Step-by-step explanation:

8x + y = 2020

Subtract 8x from each side

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3 years ago

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yanalaym [24]

Hi there! :)

Step-by-step explanation:

$SLOPE=\frac{Y_2-Y_1}{X_2-X_1}=\frac{RISE}{RUN}$

$\frac{2-(-4)}{5-2}=\frac{6}{3}=2$

Therefore, the slope is 2.

Final answer is 2.

*The answer must have a positive sign.*

I hope this helps you!

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3 years ago

Cos(0.5)+cos(0.5+2(3.14159265))+cos(0.5+4(3.14159265))

aleksandr82 [10.1K]

Answer:

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Step-by-step explanation:

First, note that 3.1415... is p, so 2(3.1415...) is 2pi and 4(3.1415...) is 4pi.

2pi and 4pi are full rotations, which will lead to the same cosine (i.e. cos(x) = cos (x+2pi) = cos(x+4pi) = ... = cos (x+2k*pi)).

So, the expression equals cos0.5 + cos 0.5 + cos0.5 = 3cos0.5 = 3(0.87758256189) = 2.63274768567

I hope this helps! :)

7 0

3 years ago

Please help thanks!!!

lora16 [44]

$probablity \: of \: \: six = 29 : 150$

<h2>hope it helps you ❣❣ </h2>

<h2>Mark me as brainliest</h2>

in fraction=29/150

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Nonamiya [84]

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3 years ago