Use an Addition or Subtraction Formula to write the expression as a trigonometric function of one number. sin 3π /7 cos 2π/ 21 − cos 3π/ 7 sin 2π/ 21

Answers

Answer 1

Answer:

sin(3π/7 - 2π/21)

Step-by-step explanation:

Given

sin 3π /7 cos 2π/ 21 − cos 3π/ 7 sin 2π/ 21

Required

Write a trigonometry formula for the expression

Using sine formula, we have:

sin(A - B) = sinAcosB - cosAsinB

The above formula can be applied to the given expression where

A = 3π/7

B = 2π/21

So, the trigonometry formula is:

sin 3π /7 cos 2π/ 21 − cos 3π/ 7 sin 2π/ 21= sin(3π/7 - 2π/21)

Answer 2

Answer:

sin(π/3), exact value √3/2

Step-by-step explanation:

21 divided by 7 is 3, 3 - 2= 1, 1 is = π


Related Questions

if 70kg is 20% of peter's weight, then what is peter's total weight!?​

Answers

50kg



Peter’s total weight is 50kg

ayme built a box in the shape of a rectangular prism with the dimensions shown. What is the volume of the box, in cubic inches? A rectangular prism has a length of 8 inches, a width of 2 inches, and a height of 4 inches. Use the formula V = l w h, where V represents the volume, l represents the length, w represents the width, and h represents the height. Inches cubed

Answers

Answer:

[tex]64(in)^{3} [/tex]

Step-by-step explanation:

The volume of a box is equal to the length l times the width w times the height h.

[tex](lenght) \times (width) \times (height)[/tex]

Substitute the values of the length l=8, the width w=2, and the height h=4 into the formula.

[tex]8 \times 2 \times 4[/tex]

Multiply 8 by 2.

[tex]16 \times 4[/tex]

Multiply 16 by 4.

[tex]64 {in}^{3} [/tex]

Hence, the volume of the rectangle prism is 64(in)³.

Answer:

64 in³

Step-by-step explanation:

Given dimensions:

l = 8 inw = 2 inh = 4 in

Volume of the prism is:

V = lwhV = 8*2*4 = 64 in³

it took bryan one hour to ride 6 1/4 miles on his bike. how far will bryan be able to ride in 3 1/2 hours?
A 21 7/8
B 9 3/4
C 5 1/2
D 9 1/4

Answers

The answer is a. Hope this helps

find the area of the shade sector of the circle

Answers

Step-by-step explanation:

We need to find the area of the shaded region. We see that the region next to that has a central angle of 120°. Also we know that angle in a straight line is 180° . So the measure of central angle of that shaded region will be 180° - 120° = 60° . Now we can use the formula of area of sector to find out the area of the shaded region.

[tex]\tt\to Area = \dfrac{\Theta}{360^o}\times \pi r^2 \\\\\tt\to Area = \dfrac{60^o}{360^o}\times \pi (8cm)^2 \\\\\tt\to Area =\dfrac{\pi \times 64}{6}cm^2\\\\\to\boxed{\orange{\tt Area_{(Shaded)}= 10.66\pi cm^2}}[/tex]

a farmer has 80 yards of land east and 100 yards west​

Answers

Answer: 8000?

Step-by-step explanation:

If your asking the area of his land, 800 yards

Total of 180 I guess? What are you trying to askkk?

Jim rent a car for the weekend can choose 1 of 2 plans the first plan has $55 initial cost an additional 0.80 per mile driven The second plan has no on the song say what it cost $0.90 per mile driven how many miles would you need to drive for the two plans to cost the Same 

Answers

however many he needs to

In Littletown, the probability that a baseball team goes to the city playoffs is
0.20. The probability that the team goes to the state playoffs given that the
team goes to the city playoffs is 0.50.
What is the probability that a randomly selected team from Littletown goes to
the city and state playoffs?
A. 0.15
B. 0.25
C. 0.10
Ο Ο
D. 0.20
SUBMIT

Answers

Answer:

C. 0.10

Step-by-step explanation:

Conditional Probability

We use the conditional probability formula to solve this question. It is

[tex]P(B|A) = \frac{P(A \cap B)}{P(A)}[/tex]

In which

P(B|A) is the probability of event B happening, given that A happened.

[tex]P(A \cap B)[/tex] is the probability of both A and B happening.

P(A) is the probability of A happening.

In this question:

Event A: Goes to the city playoffs

Event B: Goes to the state playoffs.

In Littletown, the probability that a baseball team goes to the city playoffs is 0.20.

This means that [tex]P(A) = 0.2[/tex]

The probability that the team goes to the state playoffs given that the team goes to the city playoffs is 0.50.

This means that [tex]P(B|A) = 0.5[/tex]

What is the probability that a randomly selected team from Littletown goes to the city and state playoffs?

This is [tex]P(A \cap B)[/tex]. So

[tex]P(B|A) = \frac{P(A \cap B)}{P(A)}[/tex]

[tex]P(A \cap B) = P(A)*P(B|A) = 0.2*0.5 = 0.1[/tex]

The correct answer is given by option C.

It would take ___ hours to drive 240 miles from Boston to New York, if one drives at a constant speed of 40 mph.

Answers

Answer:

6 hours.

Step-by-step explanation:

To find how many hours it would take to drive a 240 mile distance at a constant speed of 40 miles per hour, you'd divide 240 by 40 and the result of that is 6.

Answer:

6 hours

Explanation:

240/40= 6

There were 16 skittles in a bag there were 3 yellow, 4 red, 2 purple, 6 orange, and 1 green. What is the probability of pulling a red skittle (simplify your answer). The probability of a red is /

Answers

There is 4 red in the bag
Total skittles = 16

So it will be 4/16
Simplify = 1/4

Multiply 15 by 9 then divide by 2 fraction

Answers

Answer:

15x9 is 130 but, what u mean by divided by 2 fraction?

Step-by-step explanation:

135/ 2 this is correct unless you want a mixed fraction which is 67 and 1/2

6 x 10^4 how many times as great as 3 x 10^7

Answers

Answer:

one

Step-by-step explanation:

Answer each question below 26. A pair of shoes that normally costs $85 is now on sale for 45% off. What is the sale price of the shoes?
27. After Christmas, I was able to buy lights for 60% off. How much did I pay for lights that normally cost $12?
28. This past weekend, I went to Bed, Bath & Beyond to purchase a new frying pan. I was able to use a 20% off
coupon on one item. The frying pan was originally $40. What is the sale price of the frying pan?
29. When eating at a restaurant, it is recommended that you leave a 15% tip. If my bill was $24, how much
should I leave as a tip?

Answers

Answer:

26. $46.75

27. $4.80

28. $32.00

29. $3.60

The owner of Lakewood Mall wants to know the number of people who shop at the mall more than once a week. He surveys 9696 customers and finds that 2424 of them shop at the mall more than once a week. What is the probability that the next person he surveys shops at the mall more than once a week?

Answers

Answer:

go make me a sandwhich you witch

Step-by-step explanation:

For the function f(x) = 1/4e^-x + e^x, prove that the arc length on any interval has the same value as the area under the curve.

Answers

Take an arbitrary interval [a, b], where a < b.

Compute the arc length L of y = f(x) over [a, b] :

[tex]L=\displaystyle\int_a^b\sqrt{1+\left(f'(x)\right)^2}\,\mathrm dx[/tex]

Now comptue the area A under the curve y = f(x) over [a, b] :

[tex]A=\displaystyle\int_a^bf(x)\,\mathrm dx[/tex]

We have

f (x) = 1/4 e ⁻ˣ + e ˣ   →   f ' (x) = -1/4 e ⁻ˣ + e ˣ

Then

√(1 + (f ' (x))²) = √(1 + (-1/4 e ⁻ˣ + e ˣ)²)

… = √(1 + 1/16 e ⁻²ˣ - 1/2 + e ²ˣ)

… = √(1/16 e ⁻²ˣ + 1/2 + e ²ˣ)

… = 1/4 √(e ⁻²ˣ + 8 + 16e ²ˣ)

… = 1/4 √((e ⁻ˣ + 4 e ˣ)²)

… = 1/4 (e ⁻ˣ + 4 e ˣ)

… = 1/4 e ⁻ˣ + e ˣ

… = f (x)

so both A = L for any choice of interval [a, b].

It is true that the arc length on any interval has the same value as the area under the curve.

How to prove the statement

The function is given as:

[tex]f(x) = \frac 14e^{-x} + e^x[/tex]

Differentiate the function

[tex]f'(x) = -\frac 14e^{-x} + e^x[/tex]

On any interval, the following must be true

[tex]f(x) =f'(x)[/tex]

and

[tex]f(x) = \sqrt{1 + (f'(x))^2}[/tex]

So, we have:

[tex]f(x) = \sqrt{1 + (-\frac 14e^{-x} + e^x)^2}[/tex]

Expand the exponents

[tex]f(x) = \sqrt{1 + (\frac{1}{16}e^{-2x} - \frac 12 + e^{2x})}[/tex]

Remove the bracket

[tex]f(x) = \sqrt{1 + \frac{1}{16}e^{-2x} - \frac 12 + e^{2x}}[/tex]

Evaluate the like terms

[tex]f(x) = \sqrt{\frac{1}{16}e^{-2x} + \frac 12 + e^{2x}}[/tex]

Multiply by 16/16

[tex]f(x) = \sqrt{\frac{16}{16}(\frac{1}{16}e^{-2x} + \frac 12 + e^{2x})}[/tex]

So, we have:

[tex]f(x) = \sqrt{\frac{1}{16}(e^{-2x} + 8 + 16e^{2x})}[/tex]

Take the square root of 1/16

[tex]f(x) = \frac{1}{4}\sqrt{e^{-2x} + 8 + 16e^{2x}}[/tex]

Express the radical as a perfect square

[tex]f(x) = \frac{1}{4}\sqrt{(e^{-x} + 4e^{x})^2}[/tex]

Evaluate the exponents

[tex]f(x) = \frac{1}{4} * (e^{-x} + 4e^{x})[/tex]

Evaluate the products

[tex]f(x) = \frac{1}{4}e^{-x} + e^{x}[/tex]

Hence, it has been proved that  the arc length on any interval has the same value as the area under the curve.

Read more about areas at:

https://brainly.com/question/24487155

If we used the quadratic expression below to complete a diamond, which pair of values would go on the SIDES of the diamond?
x^2 - 4x + 5
a. 5 and -1
b. -5 and 1
c. -4 and 1
d. 4 and -1
e. no solution

Answers

9514 1404 393

Answer:

  e. no solution

Step-by-step explanation:

You would be looking for factors of +5 that have a sum of -4. There are none (no solution). None of the values offered in the answer choices have a product of +5.

__

The discriminant of the quadratic is (-4)² -4(1)(5) = -4, so the roots are complex.

The slope of a line is 0, and the y-intercept is 6. What is the equation written in slope intercept form.

Answers

Answer:

y=0x+6

Step-by-step explanation:

slope intercept form is: y=mx+b

Christopher sold his dinette set for $245 through an online site, which charged him 9% of the selling price as commission. what is the commission?

Answers

Answer:

$22.05

Step-by-step explanation:

If a product has a sales commission, then one must divide the commission percent by (100) to convert the percent to a decimal. Then multiply the result by the price of the product to find the amount of money that will be given as a commission.

Applying this knowledge to the given problem, one must divide (9%) by (100) to convert to decimal form,

9% / 100 = 0.09

Now multiply the result by the price of the product (245) to find the amount given away in commission,

0.09 * 245 = 22.05

Help me but i am gonna know the answer cause i know it

Answers

Answer:

D. 12

Step-by-step explanation:

93/3 = 31

155/5 = 31

248/8 = 31

In every case, you see that the number of pages is 31 times the number of hours.

For 372 pages, the number of hours is 372/31 = 12

Check: 372/12 = 31

Answer: D. 12

Why is 6P4 = 360 but 6C4 = 15?

Answers

Short answer (I write nPr = P(n, r) and nCr = C(n, r) ):

P (6, 4) = 6! / (6 - 4)! = 6! / 2! = 720 / 2 = 360

C (6, 4) = P (6, 4) / 4! = 6! / (4! (6 - 4)!) = 360 / 24 = 15

Long answer:

P(n, r) counts the number of permutations of n objects taken r at a time, given by

P(n, r) = n ! / (n - r )!

A permutation is a unique arrangement of objects such that the order in which they are arranged is taken into account. For example, if the objects in question are the numbers in the set {1, 2, 3}, then

• there are 3! = 6 total possible permutations if we take all 3 numbers at once:

123, 132, 213, 231, 312, 321

• there are 3!/(3-2)! = 3!/1! = 6 total permutations if we only take 2 numbers at once:

12, 13, 21, 23, 31, 32

• there are 3!/(3-1)! = 3!/2! = 3 total permutations if we take only 1 number at a time:

1, 2, 3

• and there is 3!/(3-0)! = 3!/3! = 1 way of permuting the 3 numbers without taking any of them:

(the permutation itself is just empty space)

By contrast, C(n, r) counts the combinations of n items taken r at a time, given by

C(n, r) = P(n, r) / r !

A combination is like a permutation, but the order of the objects doesn't matter. Continuing with the previous example of arrangements of the numbers from {1, 2, 3}, we have

• 3! / (3! (3-3)!) = 1 combination taking all 3 numbers at once:

123

(the other 5 permutations listed earlier are made up of the same numbers, so we consider them duplicates)

• 3! / (2! (3-2)!) = 3 combinations taking only 2 numbers at once:

12, 13, 23

• 3! / (1! (3-1)!) = 3 combinations taking only 1 number:

1, 2, 3

• 3! / (0! (3-0)!) = 1 combination taking none of them:

(again, empty space)

The main point is that the order of objects is considered across permutations, while it's ignored across combinations.

Janessa is playing a board game with two friends. Using a single die, one friend rolled a four, and the other friend rolle
a three. Janessa needs to roll a number higher than both friends in order to win the game, and she wants to calculate
her probability of winning.
How many desired outcomes should Janessa use in her probability calculation?

A. 3
B. 6
C. 4
D. 2

Answers

Answer:

D. 2

Step-by-step explanation:

The only possible outcomes that Janessa could possibly calculate would be 5 and 6. This is because a single die has 6 possible outcomes. If Janessa's friends rolled a 3 and a 4, and Janessa needs to roll something higher, then the only higher possible outcomes would be a 5 or a 6. Meaning that Janessa can only use a total of 2 desired outcomes for her to actually win the game.

Answer:

sorry i need more points

Step-by-step explanation:

Estimate 85.77-62.396 by first rounding each number to the nearest whole number

Answers

Answer:

24

Step-by-step explanation:

85.77-62.396 estimated by rounding each number to the nearest whole number is 24. I got this by first rounding 85.77 to 86. I then rounded 62.396 to 62. Next, I did 86-62= 24.

So, the answer is 24.

Answer:

23.000

Step-by-step explanation:

8-6=2

5-2=3

So you know that 23.000 is the roaded answer, you can just ignore the digits behind the decimal point in order to round

you decide to go to a star gazing event there are 12 people in the group

Answers

Answer:

whts the question??

Step-by-step explanation:

Is urgent What is the equation of the line, in point-slope form, that goes through (2, -1)
and is perpendicular to y = 5x + 3?
A. Y+ 1 = 5(x - 2)
O B. y-1--5(x-2)
C. »+1-- *(x-2)
O D. v-2-- }(x+1)

Answers

Answer:

c. y + 1 = -⅕(x - 2)

Step-by-step explanation:

To write the equation in point-slope form, we need to know the slope (m) and coordinates of a point the line passes through.

The equation would be in the form of y - b = m(x - a).

(a, b) = (2, -1)

Since the line is perpendicular to y = 5x + 3, the slope will be the negative reciprocal of 5 which is -⅕

m = -⅕.

Substitute a = 2, b = -1, and m = -⅕ into y - b = m(x - a).

Thus:

y - (-1) = -⅕(x - 2)

y + 1 = -⅕(x - 2)

What is the interquartile range?
.
• minimum value = 22
Qı = 34
• median = 35
Q3 = 38
• maximum value = 40

Answers

Step-by-step explanation:

[tex]interquartile \: range = \frac{1}{2} (Q _{3} - Q _{1} ) \\ = \frac{1}{2} (38 - 34) \\ = \frac{1}{2} (4) \\ = 2[/tex]

Answer:

The other dude made 0 sence

Step-by-step explanation:

Its 12

What are the ordered pairs of the solutions for this system of equations?

Answers

Answer:

( 4, 11 ) , ( - 4, 27 )

Step-by-step explanation:

f(x) = x² - 2x + 3

f(x) = - 2x + 19

x² - 2x + 3 = - 2x + 19

x² - 16 = 0

( x + 4 )( x - 4 ) = 0

[tex]x_{1}[/tex] = - 4

[tex]x_{2}[/tex] = 4

f(x) = [tex]y_{1}[/tex] = - 2( - 4 ) + 19 = 27

[tex]y_{1}[/tex] = 27

f(x) = [tex]y_{2}[/tex] = - 2( 4 ) + 19 = 11

[tex]y_{2}[/tex] = 11

( 4, 11 ) , ( - 4, 27 )

The graph shows the distance in miles, d, a car travels in hours. ​ ​ Explain why the graph does or does not represent a proportional relationship between the variables d and t.

Answers

Answer:

The graph shows a proportional relationship because t=50, and that pattern follows.

Step-by-step explanation:

The graph shows a proportional relationship because t=50, and that pattern follows.

The graph represent a proportional relationship between the variables d and t as distance in miles, d a car travels is proportional to the time in hours t.

What is the speed of a body?

The speed of a body is the rate at which it covers the total distance in the time taken. The speed of the body is given as,

[tex]s=\dfrac{d}{t}[/tex]

Here, (d) is the distance travelled by the body and (t) is the time taken by the body to cover that distance.

The graph shows the distance in miles, d, a car travels in hours. Rewrite the above formula, ​considering it for the car,

[tex]s=\dfrac{d}{t}\\t\times s={d}[/tex]

In this formula, distance in miles, d, is directly proportional to the time taken by car in hours.

It is because as the car moves, the time start to pass and so the distance car start to cover the distance. In more time, the car will cover more distance with same speed.

Thus, the graph represent a proportional relationship between the variables d and t as distance in miles, d a car travels is proportional to the time in hours t.

Learn more about the speed here:

https://brainly.com/question/359790

#SPJ2

Perform the following subtraction - 1/2 - (- 7/10)

Answers

Answer:

1.2

I t is the answer

Help me solve for x. 16^x = x^2​

Answers

Hello! Let’s begin, But before that, I hope you can mark me as the brainliest, just a hope.


x * 2^4x = x^2

2^4x = x

I’m afraid you can’t simplify more, but it could be

2^2x/2 = root x

you could solve for it yourself, because the other guy is not likely to answer.

(5^{-8})(5^{-10})=(5
−8
)(5
−10
)=

Answers

Answer:

1

3814697265625

Decimal Form:

2.62144 ⋅ 10 / 13

Step-by-step explanation:

Rewrite the Cartesian equation y=-3 as a polar equation.

Answers

r

sin

θ

=

3

Explanation:

Imagine we have a point  

P

with Rectangular (also called Cartesian) coordinates  

(

x

,

y

)

and Polar coordinates  

(

r

,

θ

)

.

The following diagram will help us visualise the situation better:

https://keisan.casio.com/exec/system/1223526375

https://keisan.casio.com/exec/system/1223526375

We can see that a right triangle is formed with sides  

x

,  

y

and  

r

, as well as an angle  

θ

.

We have to find the relation between the Cartesian and Polar coordinates, respectively.

By Pythagora's theorem, we get the result

r

2

=

x

2

+

y

2

The only properties we can say about  

θ

are its trigonometric functions:

sin

θ

=

y

/

r

y

=

r

sin

θ

cos

θ

=

x

/

r

x

=

r

cos

θ

So we have the following relations:

r

2

=

x

2

+

y

2

y

=

r

sin

θ

x

=

r

cos

θ

Now, we can see that saying  

y

=

3

in the Rectangular system is equivalent to say

r

sin

θ

=

3

Answer link

Jim G.

May 19, 2018

r

=

3

sin

θ

Explanation:

to convert from  

cartesian to polar

x

x

=

r

cos

θ

and  

y

=

r

sin

θ

r

sin

θ

=

3

r

=

3

sin

θ

Other Questions
How do I troll my teacher just found out their side job is a P05N actor speed of light is approximately 3x10^8 meters per second. While solving a problem,Cara used 3x 10^10 meters per second for the speed of light and got the incorrect answer.By which factor should Cara multiply her answer in order to get the correct answer? PLS ANSWER FAST, I'LL GIVE BRAINLIESTIn the healthcare field, there are face-to-face types of jobs and behind-the-scenes jobs. What is the difference between the two? PLEASE give an example of each with your answer. What do you think was the best method to leave East Germany and escape to West Berlin? Howwould you do it? Be as detailed as possible. Radio waves travel at the speed of light. What is the wavelength of a radio signal with a frequency of 9.45 x 10^7 Hz? Angles in triangles Question is in the photo PLSSS HELPPPP I WILLL GIVE YOU BRAINLIEST!!!!!! PLSSS HELPPPP I WILLL GIVE YOU BRAINLIEST!!!!!! PLSSS HELPPPP I WILLL GIVE YOU BRAINLIEST!!!!!! PLSSS HELPPPP I WILLL GIVE YOU BRAINLIEST!!!!!!PLSSS HELPPPP I WILLL GIVE YOU BRAINLIEST!!!!!! PLSSS HELPPPP I WILLL GIVE YOU BRAINLIEST!!!!!! PLSSS HELPPPP I WILLL GIVE YOU BRAINLIEST!!!!Write, agree or disagree after each statement then write a sentence or two about why you agree or disagree. If you dont know which side you are on explain why you cannot decide.People who do cruel things can still be good people. . O est-ce que tu habitais? Jans family has 3/4 of a cake left. How many members of her family can get 1/4 of what is left? Find the solutions of the equation f(x)=(x+3)(x-b)A: 3 and -bB: 3 and bC: -3 and -bD:-3 and b Which statement best describes whether the function is linear or nonlinear? What was one effect of roma expansion on roman society 1. Name two ways of applying forces ? Which of the following was NOT a social problem the Prohibition movement focused on improving: A. Unemployment C. Teenage Pregnancy B. Violence D. Poverty The question is attached in the photo PLEASE HELP ASAP!!!!!!THIS IS DUE TODAY!!!!!!!!!!!!*** I will make you brainiest if the answer is correct *** "what do fish have to do with anything?" which sentence best identifies the theme of the text? Can I get help with this problem please? PLEASE PLEASE HELP WILL GIIVE BRAINLIESTI AM BEING TIMED A pair of shoes that normally sells for $85.00 goes on sale for 35% off. Season thinks that the sale price should be $50.00 but Melanie disagrees and says the price should be $55.25. Aiyanna says they are both wrong and decides the price should be $29.75. Who is correct and why? Read this excerpt from Vachel Lindsays poem In Praise of Johnny Appleseed.In the days of President Washington,The glory of the nations,Dust and ashes,Snow and sleet,And hay and oats and wheat,Blew west,Crossed the Appalachians,Found the glades of rotting leaves, the soft deer-pastures,The farms of the far-off futureIn the forest.How does this allusion reinforce the meaning of the excerpt?The allusion offers images of nature for the excerpt.The allusion lends patriotic pride to the excerpt.The allusion recounts historical fact for the excerpt.The allusion adds weather detail to the excerpt.