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3 years ago

50 points please give step by step instruction

Mathematics

1 answer:

fenix001 [56]3 years ago

8 0

Answer:

 x = 90, 199.5, 270, 340.5 degrees

Step-by-step explanation:

cos2x + 2sinx = sin^2x

Change cos2x to 1 - 2sin^2x:

1 - 2sin^2x + 2 sinx = sin^2x

Shift the terms to make it a quadratic equation:

3 sin^2x - 2sinx - 1 = 0

Factorise the quadratic equation:

(sinx - 1)(3sinx + 1) = 0

sin x = 1 or sin x = -1/3

Solve for sin x = 1:

From graph of sin x, x = 90 and 270 degrees when sin x = 1.

x = 90, 270 degrees

Sin x = -1/3

Basic angle = sin inverse (1/3)

= 19.471 degrees

Since sin x < 0, x is in the 3rd or 4th quadrant

x = 180 + 19.471, 360 - 19.471

x = 199.5, 340.5

Hence, x = 90, 199.5, 270, 340.5 degrees

[Sorry if I am wrong :( ]

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4x-5=7+4y How do you solve?

solong [7]

solve for x.

4x−5=7+4y

Add 5 to both sides.

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Divide both sides by 4.

4x/4=4y+12/4

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3 years ago

One sample has a mean of and a second sample has a mean of . The two samples are combined into a single set of scores. What is t

Murrr4er [49]

Answer:

a) For this case we can use the definition of weighted average given by:

$M = \frac{ \bar X_1 n_1 + \bar X_2 n_2}{n_1 +n_2}$

And if we replace the values given we have:

$M = \frac{8*4 + 16*4}{4+4}= 12$

b) $M = \frac{8*3 + 16*5}{3+5}= 13$

c) $M = \frac{8*5 + 16*3}{5+3}= 11$

Step-by-step explanation:

Assuming the following question: "One sample has a mean of M=8 and a second sample has a mean of M=16 . The two samples are combined into a single set of scores.

a) What is the mean for the combined set if both of the original samples have n=4 scores "

For this case we can use the definition of weighted average given by:

$M = \frac{ \bar X_1 n_1 + \bar X_2 n_2}{n_1 +n_2}$

And if we replace the values given we have:

$M = \frac{8*4 + 16*4}{4+4}= 12$

b) what is the mean for the combined set if the first sample has n=3 and the second sample has n=5

Using the definition we have:

$M = \frac{8*3 + 16*5}{3+5}= 13$

c) what is the mean for the combined set if the first sample has n=5 and the second sample has n=3

Using the definition we have:

$M = \frac{8*5 + 16*3}{5+3}= 11$

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3 years ago

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sergejj [24]

Answer:

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Step-by-step explanation:

Answer: The correct answer is inches because radius and Diameter are always given in a single form unit of measure.

Inches units represents the diameter of the circle.

Please mark brainliest

Hope this helps.

3 0

3 years ago

400

Feliz [49]

Answer:

Step-by-step explanation:

7 0

3 years ago

If a distribution has a mean of 100 and a standard deviation of 15, what value would be 2 standard deviations from the mean

sveticcg [70]

The value that is 2 standard deviations from the mean is; 130

<h3>What is Empirical Rule?</h3>

For this question, we will use Z-score and as such whether the value is below or above mean (shown by positive or negative sign) and by how much (times the standard deviation).

Thus;

Calculated value = μ + zσ

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Hence, the value that would be +2 standard deviations from the mean is;

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Calculated value = 130

Read more about Empirical Rule at; brainly.com/question/10093236

4 0

2 years ago