2^x + 2^-x =5/2 pls I need d. ans

Mathematics

1 answer:

yKpoI14uk [10]3 years ago

6 0

Answer:

x= 1, -1

Step-by-step explanation:

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What is the measure of

nadezda [96]

Answer:

It's 15°

Step-by-step explanation:

BC+60°+85°+200° =360°

BC+345°=360°

BC=360°-345°

Bc=15°

5 0

3 years ago

You want to obtain a sample to estimate a population proportion. At this point in time, you have no reasonable preliminary estim

prohojiy [21]

Using the z-distribution, it is found that a sample size of 3,385 is required.

<h3>What is a confidence interval of proportions?</h3>

A confidence interval of proportions is given by:

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

The margin of error is:

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which:

$\pi$ is the sample proportion.

z is the critical value.

n is the sample size.

In this problem, we have a 98% confidence level, hence $\alpha = 0.98$ , z is the value of Z that has a p-value of $\frac{1+0.98}{2} = 0.99$ , so the critical value is z = 2.327.

We have no prior estimate, hence $\pi = 0.5$ is used, which is when the largest sample size is needed. To find the sample size, we solve the margin of error expression for n when M = 0.02, hence: