[tex] \rm \int_{0}^{ \pi } \cos( \cot(x) - \tan(x)) \: dx \\ [/tex]​

Answers

Answer 1

Replace x with π/2 - x to get the equivalent integral

[tex]\displaystyle \int_{-\frac\pi2}^{\frac\pi2} \cos(\cot(x) - \tan(x)) \, dx[/tex]

but the integrand is even, so this is really just

[tex]\displaystyle 2 \int_0^{\frac\pi2} \cos(\cot(x) - \tan(x)) \, dx[/tex]

Substitute x = 1/2 arccot(u/2), which transforms the integral to

[tex]\displaystyle 2 \int_{-\infty}^\infty \frac{\cos(u)}{u^2+4} \, du[/tex]

There are lots of ways to compute this. What I did was to consider the complex contour integral

[tex]\displaystyle \int_\gamma \frac{e^{iz}}{z^2+4} \, dz[/tex]

where γ is a semicircle in the complex plane with its diameter joining (-R, 0) and (R, 0) on the real axis. A bound for the integral over the arc of the circle is estimated to be

[tex]\displaystyle \left|\int_{z=Re^{i0}}^{z=Re^{i\pi}} f(z) \, dz\right| \le \frac{\pi R}{|R^2-4|}[/tex]

which vanishes as R goes to ∞. Then by the residue theorem, we have in the limit

[tex]\displaystyle \int_{-\infty}^\infty \frac{\cos(x)}{x^2+4} \, dx = 2\pi i {} \mathrm{Res}\left(\frac{e^{iz}}{z^2+4},z=2i\right) = \frac\pi{2e^2}[/tex]

and it follows that

[tex]\displaystyle \int_0^\pi \cos(\cot(x)-\tan(x)) \, dx = \boxed{\frac\pi{e^2}}[/tex]


Related Questions

Find the sum of a finite arithmetic sequence from n=1 to n=5 using the expression -3(4)^n-1

Answers

Answer:

Step-by-step explanation:

Arithmetic sequaence:

[tex]\sf a_n = -3(4)^n - 1\\\\a_1=-3*4^1 -1\\\\ = -3*4 - 1\\\\ = -12 - 1\\\\a_1=-13[/tex]

[tex]a_2 = -3*4^2-1\\[/tex]

    = -3*16 -1

     = -48 - 1

    = -49

difference = second term - first term

                 = -49 -(-13)

                = -49 + 13

             d = -36

[tex]\boxed{S_n=\dfrac{n}{2}[2a + (n-1)d]}[/tex]

[tex]\sf S_5=\dfrac{5}{2}*[2*(-13} + 4*(-36)]\\\\ =\dfrac{5}{2}[-26-144]\\\\=\dfrac{5}{2}*(-270)[/tex]

= 5*(-135)

= -675

Point q is located on the coordinate grid at (-9.73,-3.32) in which quadrant is point q called

Answers

Answer:

  III

Step-by-step explanation:

The signs of both x and y are negative in the 3rd quadrant.

__

x-values are negative in the left half-plane.

y-values are negative in the bottom half-plane.

Both coordinates are negative in the lower-left quadrant, number III.

A data set is normally distributed with a mean of 8.1 and a standard deviation of 3.8.
What percentage of the data is above 8.6?
Enter your answer as a number to the nearest whole percentage, like this: 42%

Answers

Answer:

  45%

Step-by-step explanation:

Your graphing calculator, statistics app, or spreadsheet can tell you that 45% of the normally-distributed data is above 8.6 when the mean is 8.1 and the standard deviation is 3.8.

CAN SOMEONE HELP PLS?? I rlly dont get this.

Answers

The little square on the angle means that the entire angle is 90 degrees

The larger angle is made up of two angles of measure 'x - 18' and 'x'

Let's put that into an equation form:

     (x - 18) + (x) = 90

        2x - 18 = 90

           2x = 108

            x  = 54

So x = 54

Hope that helps!

Which of the following is true of the numbers 4 and 10?

A. The greatest common factor is
B. The least common multiple is
C. The greatest common factor is 20.
D. The least common multiple is 40.​

Answers

Answer:

None

Step-by-step explanation:

Answer is isn't there

the gcf = 2

the LCM = 20

What’s the difference between 4, 7/9 and 2 1/2

Answers

[tex]\huge \mathbb \orange{ANSWER} [/tex]

[tex] \: \: \: \: \: \: \: \: \: \: \: \: \: \mathsf \purple{4 \frac{7}{9} - 2 \frac{1}{2} }[/tex]

[tex] \blue\implies \mathsf \pink{ 2(\frac{43}{9}) - (\frac{5}{2} )9 }[/tex]

[tex] \blue \implies \mathsf \purple{ \frac{86}{18} - \frac{45}{18} }[/tex]

[tex] \blue \implies \mathsf \pink{ \frac{41}{18} = 2 \frac{5}{18} }[/tex]

Please help i wan't a good grade but I can't figure this out.

Answers

Answer:

angle DCE

Angle DEC

Angle ABF

Step-by-step explanation:

you had the wrong order

Which expression is equivalent to the following complex fraction?

Answers

Consider the fraction first ;

[tex]{:\implies \quad \sf \dfrac{\dfrac{3}{(x-1)}-4}{2-\dfrac{2}{(x-1)}}}[/tex]

[tex]{:\implies \quad \sf \dfrac{\dfrac{3-4(x-1)}{\cancel{(x-1)}}}{\dfrac{2(x-1)-2}{\cancel{(x-1)}}}}[/tex]

[tex]{:\implies \quad \sf \dfrac{3-4x+7}{2(x-1-1)}}[/tex]

[tex]{:\implies \quad \boxed{\bf{\dfrac{-4x+7}{2(x-2)}}}}[/tex]

Hence, Option B) is required answer

help help help help math math

Answers

Answer:

2

Step-by-step explanation:

the line is straight and is set on 2 so y<2

Use the distributive property to write the following expressions in expanded form. 4(x +y)

Answers

Answer:

4x+4y

Step-by-step explanation:

Answer:

4x + 4y

Step-by-step explanation:

To do this you need to know that the number (or variable) on the outside of the parenthesis must be multiplied to all of the numbers/variables on the inside of the parenthesis.

So here, you want to multiply x by 4:

4x

Then multiply y by 4:

4y

And because the expression is adding the x and y, it comes out as:

4x + 4y

Box size | number of mufffons
Small. 4
Medium. 6
Large. 8
Extra large 12

How many muffins are needed to fill all the boxes? Show your work

Answers

30
4 + 6 = 10
10 + 8 = 18
18 + 12= 30

or 4 + 6 + 10 + 8 + 12 = 30

A 22° B 54° С What is the measure of AD? O 108° 0 27° 126 54°​

Answers

Answer:

A. 108

sorry if im wrong but if u am I'm so sorry

A car travels 80 miles on 3 gallons of gas. At the same rate (in miles per gallon) l, how many miles will the car be expected to travel on 5 gallons of gas?

A. 48

B. 130

C. 133 1/5

D. 160

Answers

Answer:

C

Step-by-step explanation:

What angles are acute GFE mlk dbc dba

Answers

Answer:

d and a

Step-by-step explanation:

an acute is an angle less than 90 degrees. a 90 degree angle is a right angle (klm) the only 2 angles smaller than (klm) are (gfe) and (dba)

Find the simple interest on the loan of $2500 for 2 years at 5%.
$
(Simplify your answer. Round to the nearest cent as needed.)

Answers

Answer:

Step-by-step explanation:

simple interest=prt

p=principle amount

r=rate

t=time

here p=$2500

r=5 %=0.05

t=2 years

simple interest=2500×2×0.05=$250

The simple interest on the loan of $2500 for 2 years at 5% is $250

How to determine the value?

The formula for calculating simple interest is expressed as;

I = PRT/100

Such that the parameters of the formula are;

P is the principal amountI is the simple interestR is the interest rateT is the time

Now, substitute the values, we get;

Simple interest = 2500 × 5 × 2/100

Multiply the values

Simple interest =25, 000/100

Simple interest =$250

Learn about simple interest at: https://brainly.com/question/25793394

#SPJ2

NEED HELP ASAP The salaries of Nathan and Trisha are in the ratio of 5:9. Trisha's salary is £16800 more than Nathan's. Find Nathan's salary.​

Answers

Answer:

From the ratio

The difference is 9 - 5 = 4

Hence Trisha has 4 units more than Nathan and this resulted to 16800

Therefore 1 unit will be

16800 / 4 = 4200


Nathan’s salary is 5 units

5 * 4200 = 21000

How do you solve this?
2sinXcosX=sinX

Answers

Answer: X=60°
2sinXcosX = sinX
Divide through by 2sinX
cosX = 1/2
X = cos-1(1/2)
X= 60°

-0.5(14a - 22) = ? this for my work, please help me.

Answers

Answer:

-7a+11

Step-by-step explanation:

Given f(x) and g(x) = f(x) + k, use the graph to determine the value of k.

Answers

Answer:

  k = 3

Step-by-step explanation:

The value of k is the amount by which the function f(x) is translated upward to give the function g(x). We can compare y-intercepts to see that the y-intercept of g(x) is 5 -2 = 3 units more than the y-intercept of f(x). This means ...

  g(x) = f(x) +3

Comparing to ...

  g(x) = f(x) +k

we see that k = 3.

135.99 rounded to two significant figures

Answers

Answer:

1.3×10^1

Step-by-step explanation:

For this, you need to use scientific notation

First, let's round up the decimal points

135.99 = ~ 136

1.3 ×.10^1

A very slow man walks

20 cm.in 0.5 left, what his

velocity in meter per second?

Answers

Displacement(d)=0.2m
Time taken(t)= 30 s(1min=60 s)
Velocity (v)=?
We know that,
Velocity (v) = d/t
=0.0067

Does anyone know the answers? Need help!!

Answers

Answer:

nice handwriting

Step-by-step explanation:

What is the range of this data set?

36.6, 39.8, 33.3, 34.8, 35.8, 39.6, 36.7, 36.9, 37.5, 32.2, 33.1, 33.3

Answers

Answer:

Step-by-step explanation:

39.8 - 32.2 = 7.6

Range is subtracting the highest and lowest numbers by each other .

Based on the calculations, the range for this data set is equal to 7.6.

What is a range?

In Mathematics, a range can be defined as the difference between the highest number and the lowest number contained in a data set.

Mathematically, range is calculated by using this formula;

Range = Highest number - Lowest number

From the given data set, we have:

Highest number = 39.8.Lowest number = 32.2.

Substituting the given parameters into the formula, we have;

Range = 39.8 - 32.2

Range = 7.6.

Read more on range here: https://brainly.com/question/9393969

help me please mark U as BRAINLIEST​

Answers

Hope this helps. Good luck

Which of the binomials below is a factor of this trinomial?

x^2 + 8x + 16

A. x + 4

B. x - 4

C. x + 8

D. x - 8

Answers

The answer is A.

Pick A.

Good luck

What is a2+b2+c2? Thank you for your help.

Answers

Answer:

Pythagoras theorem

Step-by-step explanation:

dhebbd

A store sells a workout outfit that consists of a jacket, a t-shirt, and a pair of shorts. The store purchases the jacket for $34, the t-shirt for $9, and the shorts for $12. The percent of markup is 28%. Find the selling price of the outfit.

PS: include show work please I have to submit this in like 3 hours thankyou

Answers

Answer:

The Outfit costs $70.4.

Step-by-step explanation:

Add the selling price together

34 + 9 + 12 = 55

Multiply by the markup (Profit)

100% = 1

28% = 0.28

55 x 1.28 = 70.4

Kaya rented a limousinefor prom. There was a one-time charge of $100 plus an hourly rate of $50 per hour. Her
total cost for the night was $300. How many hours did she rent the limo?

Answer using 2 step equations and X as variable

Answers

Let X be number of hours rented and C be total cost.
C = 50X + 100
Since C = 300,
50X + 100 = 300
50X = 200
X = 4 hours
300=100+50x
x=4
She rented the limo for 4 hours($200) with the one time charge of $100

Geometry: Trig Pile Up Activity

Answers

The measure of the unknown angle is 53 degrees.

The length of the unknown side of the blue triangle is 4.43 cm

Right angle triangle

Right angle triangle have one of its angles as 90 degrees.

The sum of angle in a triangle is 180 degrees.

Therefore, the measure of the unknown angle can be calculated as follows:

let

x = unknown angle

x = 180 - 90 - 37 = 53°

Therefore, let's find the unknow length of the blue triangle.

tan 53 = opposite / adjacent

tan 53 = 6.9 / a

a = 6.9 / 1.327

a = 5.1996985682

a = 5.2

The green triangle hypotenuse = 5.2 + (5.2 - 2.6) = 7.8 cm

Therefore,

sin 59 = opposite / 7.8

opposite = 7.8 × 0.8571673007

opposite = 6.68590494548

opposite side = 6.69 cm

The hypotenuse of the blue triangle = 6.69 - 2 = 4.69 cm

Therefore,

sin 71 = x / 4.69

x = 4.69 × 0.94551857559

x = 4.43448211956

x = 4.43 cm

learn more on right triangle here: https://brainly.com/question/7894175

Write the rate in lowest terms.
During a bad storm there was 2 in of rain in 4 hr.
The rate in lowest terms is_____?

Answers

Answer:

1/2 in/hr

Step-by-step explanation:

2 in / 4h   =   1/2 inch per hour

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