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3 years ago

Consider the set of points defined by z = 5 cos(theta) + 3i sin(theta).

Mathematics

1 answer:

vitfil [10]3 years ago

4 0

Answer:

This is an ellipse.

Step-by-step explanation:

$z=5cos(\theta)+3isin(\theta)$

Applying the angle values in intervals of right angles (90°), the resulting set of values for z are:

$\theta = 0,90,180,270,360$

$z=5,3i,-5,-3i,5$ (again)

If you look at the plot, you will observe how these values represent points in the xy plain. All of them belong to either the x or the y axis.

The resulting figure for the whole set of values of $\theta$ is in fact an ellipse.

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Find Ms. Buggie's mistake in the following problem. Then, give what the correct answer should be.

sdas [7]

Answer:

Mrs. Buggie should have Subtracted 13 instead of adding 13

LKA = 94°

Step-by-step explanation:

Lets work backwards from the equation so far:

40 = x+ 13

x + 13 = 40

We should subtract 13 because we are adding a number and 13 to 40

Imagine this:

You have 5 apples, but you bought some more and now you have 10

equation would be:

5+x = 10

subtract 5 from 10 to get 5

So you bought 5 apples

Back to the Question:

40 - 13 = 27

3(27) + 13 = 81+13 = 94°

Answer = 94°

If my answer is incorrect, pls correct me!

If you like my answer and explanation, mark me as brainliest!

-Chetan K

8 0

3 years ago

Advandia is a drug used to treat diabetes, but it may cause an increase in heart attacks among a population already susceptible.

sergiy2304 [10]

Answer:

a) The proportions are not form matched-pairs data.

b) The null hypothesis failed to be rejected.

There is not enough evidence to support the claim that there is evidence of a significant increase in the proportion of people who suffer heart attacks when using Avandia compared to other treatments.

Step-by-step explanation:

a) Two data sets are "paired" when the following one-to-one relationship exists between values in the two data sets:

Each data set has the same number of data points.

Each data point in one data set is related to one, and only one, data point in the other data set.

None of this conditions apply in this case, so the proportions are not form matched-pairs data.

b) This is a hypothesis test for the difference between proportions.

The claim is that there is evidence to suggest that there is a significant increase in the proportion of people who suffer heart attacks when using Avandia compared to other treatments.

Then, the null and alternative hypothesis are:

$H_0: \pi_1-\pi_2=0\\\\H_a:\pi_1-\pi_2> 0$

The significance level is 0.05.

The sample 1 (Avindia treatment), of size n1=1456 has a proportion of p1=0.0185.

$p_1=X_1/n_1=27/1456=0.0185$

The sample 2 (other treatment), of size n2=2895 has a proportion of p2=0.0142.

$p_2=X_2/n_2=41/2895=0.0142$

The difference between proportions is (p1-p2)=0.0044.

$p_d=p_1-p_2=0.0185-0.0142=0.0044$

The pooled proportion, needed to calculate the standard error, is:

$p=\dfrac{X_1+X_2}{n_1+n_2}=\dfrac{27+41}{1456+2895}=\dfrac{68}{4351}=0.0156$

The estimated standard error of the difference between means is computed using the formula:

$s_{p1-p2}=\sqrt{\dfrac{p(1-p)}{n_1}+\dfrac{p(1-p)}{n_2}}=\sqrt{\dfrac{0.0156*0.9844}{1456}+\dfrac{0.0156*0.9844}{2895}}\\\\\\s_{p1-p2}=\sqrt{0.00001+0.00001}=\sqrt{0.00002}=0.004$

Then, we can calculate the z-statistic as:

$z=\dfrac{p_d-(\pi_1-\pi_2)}{s_{p1-p2}}=\dfrac{0.0044-0}{0.004}=\dfrac{0.0044}{0.004}=1.1$

This test is a right-tailed test, so the P-value for this test is calculated as (using a z-table):

$P-value=P(z>1.1)=0.1358$

As the P-value (0.1358) is bigger than the significance level (0.05), the effect is not significant.

The null hypothesis failed to be rejected.

There is not enough evidence to support the claim that there is evidence to suggest that there is a significant increase in the proportion of people who suffer heart attacks when using Avandia compared to other treatments.

8 0

3 years ago

Read 2 more answers

Stuck, anyone can help?

expeople1 [14]

Answer:

Step-by-step explanation:

$\sqrt{x-3}$ = x - 5 ( x ≥ 3 )

( $\sqrt{x-3}$ )² = ( x - 5 )²

x - 3 = x² - 10x + 25

x² - 11x + 28 = 0

(x - 4)(x - 7) = 0

$x_{1}$ = 7

$x_{2}$ = 4

Check the answer:

1). x = 7

$\sqrt{7-3}$ = 7 - 2

√4 = 2

2 = 2

2). x = 4

$\sqrt{4-3}$ = 4 - 5

1 = - 1 (False statement) ⇒ x = 4 is an extraneous solution.

6 0

3 years ago

Will it cost more to rent from Company A or Company B if "Ali" rents the bounce house for 3 hours? 5 hours? 10 hours?

a_sh-v [17]

Answer:

3 HOURS : company A costs more

5 HOURS : Cost is the same

10 HOURS : Company B costs more

Step-by-step explanation:

Company A :

Rental fee = $100

Hourly rate = $20

Company B:

Hourly rate = $40

Cost of renting a bounce house from each company for h hours ;

Company A:

Total cost = 100 + 20h

Company B:

Total cost = 40h

If h = 3

Company A:

100 + 20(3) = $160

Company B:

40(3) = $120

FOR h = 5;

Company A:

100 + 20(5) = $200

Company B:

40(5) = $200

FOR h = 10;

Company A:

100 + 20(10) = $300

Company B:

40(10) = $400

3 0

3 years ago

If a = 7 - 4√3, find the value of a + 1/a

irga5000 [103]

Answer:

Step-by-step explanation:

To calculate a+1/a, we first need to calculate for a.

a = 7 - 4 * $\sqrt[2]{3}$

square root of 3 = 1.73

a = 7 - 4 * 1.73

a = 7 - 6.9

a = 0.1

0.1 + 1 / 0.1 = 0.1 + 10 = 10.1

Now, in case 4 wasn't being multiplied with the square root of 3, and instead, it was four root of 3, I am gonna do the calculations again:

a = 7 - $\sqrt[4]{3}$

a = 7 - 1.31

a = 5.69

5.69 + 1 / 5.69 = 5.69 + 0.17 = 5.86

Hope I Helped!

5 0

2 years ago