If alpha and beta are the complex cube roots of unity then alpha power 4 + beta power 4 + 1/ alpha.bata?

Triangle Q M N is shown. The length of Q M is 18, the length of M N is 17, and the length of Q N is 20. Law of cosines: a2 = b2

kvasek [131]

Answer:

53°

Step-by-step explanation:

17² = 18² + 20² - 2(18)(20) cos Q

289 = 324 + 400 - 720 cos Q

289 = 724 - 720 cos Q

-435 = -720 cos Q

0.6042 = cos Q

$cos^{-1} (0.6042) = Q$

Q = 52.83

3 0

4 years ago

1. If 9 students sharpen 18 pencils in 2 minutes, how many students will it take to sharpen 18 pencils in 1 minute?

Ad libitum [116K]

A) If 9 students sharpen 18 pencils in 2 minutes,Then if the time is halved, it will take twice as many men to sharpen 18 pencils.Hence it will take 18 students to sharpen 18 pencils in one minute B) y & 1/x. Then y = K/x where K is our constant of proportionality.Then K = yx. When x = -64 and y = -16 then K = -64 * -16 = 1024. Option DC) When x = 3 y = 8. So for an inverse variation K as calculated from B = 3 * 8 = 24.Then when K = 24 and y = 6; we have 24 = 6x. Hence x = 4. Option A

6 0

3 years ago

The 2nd term of an exponential sequence is 9 while the 4th term is 81.find the common ratio,the first term and the sum of the fi

Thepotemich [5.8K]

Answer:

second term: 9

4th term:81

$(3rd \: term)^{2} = 9 \times 81$

=729

$\sqrt{729} = 27$

3rd term=27

${9}^{2} = a1x27 \\ 81 = 27a1$

a1=3 the first term

$81 = 3 \times {q}^{3}$

${q}^{3} = 27$

q=3

$s = 3x \frac{1 - {3}^{5} }{1 - 3} = 364.5$

5 0

3 years ago

(5 x 10^-2) divided by (3.0 x 10^4)

vlada-n [284]

Exact form :

1

_______

600000

Decimal form :

-
1. 6 . 10 ^ -6.

If you can , can you please mark me as brainlist:)

3 0

3 years ago

In a survey conducted by the Gallup Organization, 1100 adult Americans were asked how many hours they worked in the previous we

const2013 [10]

Answer:

1) Increase the sample size

2) Decrease the confidence level

Step-by-step explanation:

The 95% confidence interval built for a sample size of 1100 adult Americans on how much they worked in previous week is:

42.7 to 44.5

We have to provide 2 recommendations on how to decrease the margin of Error. Margin of error is calculated as:

$M.E=z_{\frac{\alpha}{2} } \times \frac{\sigma}{\sqrt{n}}$

Here,

$z_{\frac{\alpha}{2} }$ is the critical z-value which depends on the confidence level. Higher the confidence level, higher will be the value of critical z and vice versa.

$\sigma$ is the population standard deviation, which will be a constant term and n is the sample size. Since n is in the denominator, increasing the value of n will decrease the value of Margin of Error.

Therefore, the 2 recommendations to decrease the Margin of error for the given case are:

Increase the sample size and make it more than 1100
Decrease the confidence level and make it lesser than 95%.

7 0

4 years ago