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-BARSIC- [3]
3 years ago
10

5cosx -2sin(x/2) +7=0Help me to find x step by steppls​

Mathematics
1 answer:
miskamm [114]3 years ago
8 0

Answer:

x = 180

Step-by-step explanation:

First, you need to know

1. Double-angle formula:

cos(2x) = cos^{2}x - sin^{2}x

2. Pythagorean identity:

cos^{2}x + sin^{2}x = 1

Back to your problem, replacing the variable by the above:

5cosx-sin\frac{x}{2}+7 = 0

5(cos^{2}\frac{x}{2}-sin^{2}\frac{x}{2}) - 2sin\frac{x}{2} + 7 = 0 By Double-angle formula

5(1 - 2sin^{2}\frac{x}{2}) - 2sin\frac{x}{2} + 7 = 0 By Pythagorean identity

Given y = \frac{x}{2}

5(1-2sin^{2}y) - 2siny + 7 = 0

10sin^{2}y+2siny-12=0

5sin^{2}y+siny-6=0

(5siny + 6)(siny - 1)=0, we know -1 < sinx < 1, for every x ∈ R

siny = 1, y =90

y = \frac{x}{2}

x = 180

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juin [17]

Answer:

2.275%

Step-by-step explanation:

The first thing to do here is to calculate the z-score

Mathematically;

z-score = (x-mean)/SD

from the question, x = 12,300 hours , mean = 11,500 hours while Standard deviation(SD) = 400 hours

Plugging the values we have;

z-score = (12,300-11,500)/400 = 800/400 = 2

Now, we want to calculate P(z ≤ 2)

This is so because we are calculating within a particular value

To calculate this, we use the z-score table.

Mathematically;

P(z ≤ 2) = 1 - P(z > 2) = 1 - 0.97725 = 0.02275

To percentage = 2.275%

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3 years ago
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Answer:

The correct answer is A. It is constant.

Step-by-step explanation:

When the x-values are between 4 and 8, this graph is constant.  This can be seen because the graph is a horizontal line, meaning it has zero slope.  Since the slope is zero, it is neither increasing nor decreasing, and is known as constant.

Hope this helps!

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3 years ago
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=$18 + (0.06 X 18)+ (0.2 X 18)

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The total price of Alyssa's meal is $22.68.

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Step-by-step explanation:

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Step-by-step explanation:

this is the answer guys.

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