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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Which of the following is a binomial?. c2 + c + 6. c2 - 16. -8c. c3 + 4c2 - 12c + 7. Which of the following is a monomial?. c2 +

vlabodo [156]

A monomial has one term, binomial has two terms, trinomial has three terms, and a polynomial has four or more terms.

Therefore, in the first question, c2-16 is the binomial while -8c is the monomial in the second question.

I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!

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3 years ago

The height H of an ball that is thrown straight upward from an initial position 3 feet off the ground with initial velocity of 9

mariarad [96]

Answer:

The ball will be 84 feet above the ground 1.125 seconds and 4.5 seconds after launch.

Step-by-step explanation:

Statement is incorrect. Correct form is presented below:

The height $h(t)$ of an ball that is thrown straight upward from an initial position 3 feet off the ground with initial velocity of 90 feet per second is given by equation $h(t) = 3 +90\cdot t -16\cdot t^{2}$ , where $t$ is time in seconds. After how many seconds will the ball be 84 feet above the ground.

We equalize the kinematic formula to 84 feet and solve the resulting second-order polynomial by Quadratic Formula to determine the instants associated with such height:

$3+90\cdot t -16\cdot t^{2} = 84$