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antoniya [11.8K]
3 years ago
10

Hi please help me with this math question​

Mathematics
1 answer:
Natasha2012 [34]3 years ago
7 0

Step-by-step explanation:

cos(3x) = sin(2x)

Use reflection.

sin(π/2 − 3x) = sin(2x)

π/2 − 3x = 2x

π/2 = 5x

x = π/10

Instead, use multiple angle formulas.

cos(3x) = sin(2x)

4 cos³x − 3 cos x = 2 sin x cos x

4 cos³x − 3 cos x − 2 sin x cos x = 0

cos x (4 cos²x − 3 − 2 sin x) = 0

cos x (4 (1 − sin²x) − 3 − 2 sin x) = 0

cos x (4 − 4 sin²x − 3 − 2 sin x) = 0

-cos x (-4 + 4 sin²x + 3 + 2 sin x) = 0

-cos x (4 sin²x + 2 sin x − 1) = 0

If t = sin(π/10), then:

4t² + 2t − 1 = 0

Solve with quadratic formula:

t = [ -2 ± √(2² − 4(4)(-1)) ] / 2(4)

t = [ -2 ± √(4 + 16) ] / 8

t = (-2 ± 2√5) / 8

t = (-1 ± √5) / 4

Since π/10 is in the first quadrant, sin(π/10) is positive.

sin(π/10) = (-1 + √5) / 4

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The greater of two numbers is 5 more than the smaller. If the
xenn [34]

Answer:

First number = 4

Second number = 9

Step-by-step explanation:

If the first number = x, the second number = x + 5.

The calculation can be expressed as follows:

x + 2(x + 5) = 22

First, expand the bracket 2(x + 5):

x + 2x + 10 = 22

Combine like terms:

3x + 10 = 22

Subtract 10 from both sides:

3x = 12

Divide both sides by 3:

x = 4

First number = 4

Second number = 4 + 5 = 9

5 0
1 year ago
I need help please help me ​
dem82 [27]

Answer:

Option A is the answer

mark me as brainliest

6 0
3 years ago
Explain how you could use a number line to determine -5 -(-3)<br><br> What is the difference?
AURORKA [14]

Answer:

The difference is -2

7 0
3 years ago
Use​ l'Hôpital's Rule to find the following limit. ModifyingBelow lim With x right arrow 0StartFraction 3 sine (x )minus 3 x Ove
steposvetlana [31]

Answer:

\lim_{x \to 0} \frac{3sinx-3x}{7x^3}=-\frac{1}{14}

Step-by-step explanation:

The limit is:

\lim_{x \to 0} \frac{3sinx-3x}{7x^3}=\frac{0}{0}

so, you have an indeterminate result. By using the l'Hôpital's rule you have:

\lim_{x \to 0} \frac{a(x)}{b(x)}= \lim_{x \to 0} \frac{a'(x)}{b'(x)}

by replacing, and applying repeatedly you obtain:

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hence, the limit of the function is -1/14

8 0
3 years ago
The owner of a bookstore orders 32 copies of a book for $12.34 each.
makvit [3.9K]
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The total cost of the books is $394.88
5 0
3 years ago
Read 2 more answers
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