Answers
Answer:
cos 2x = (√7) / 4
Step-by-step explanation:
sin x - cos x = 1/2
(sin x - cos x)² = (1/2)²
sin²x - 2 sin x cos x + cos² x = 1/4
1 - 2 sinx cosx = 1/4
2 sinx cosx = 3/4
sin 2x = 2 sinx cosx = 3/4
sin² 2x = 9/16
cos² 2x = 1 - sin² 2x = 1 - 9/16 = 7/16
cos 2x = (√7) / 4
Related Questions
A bowl of mixed vegetables contains carrots, broccoli, and cauliflower. If the bowl contains 80 vegetable pieces, and 25% of the pieces are carrots, how many carrots are in the bowl?
Answers
Answer:
Number of carrot pieces in bowl = 20
Step-by-step explanation:
Given:
Total number of vegetable pieces = 80
Percent of carrot = 25%
Find:
Number of carrot pieces in bowl
Computation:
Number of carrot pieces in bowl = Total number of vegetable pieces x Percent of carrot
Number of carrot pieces in bowl = 80 x 25%
Number of carrot pieces in bowl = 80 x 0.25
Number of carrot pieces in bowl = 20
Answer:
20
Step-by-step explanation:
I took it on Edge
What is the slope of the line passing through (-2, 4) and (3,-4)
Answers
In a lab experiment, 130 bacteria are placed in a petri dish. The conditions are such
that the number of bacteria is able to double every 8 hours. How many bacteria
would there be after 21 hours, to the nearest whole number?
Answers
Answer:
y = 802
Step-by-step explanation:
Show that n(n – 1)(n + 1) + 6n ≡ n3 + 5n
Answers
Explanation:
n(n - 1)(n + 1) + 6n = n^3 + 5n
n(n^2 - 1) + 6n = n^3 + 5n
n^3 - n + 6n = n^3 + 5n
n^3 + 5n = n^3 + 5n (proven)
Flying against the wind, an alrplane travels 4700 kilometers in 5 hours. Flying with the wind, the same plane travels 9520 kilometers in 7 hours. What is the rate of the plane in still air and what is the rate of the wind?
Answers
Answer:
i think this
Step-by-step explanation:
Let Va = the velocity of the airplane
Let Vw = the velocity of the wind
When flying with the wind:
(Va+Vw)*(4 hours) = 4000
4Va + 4Vw = 4000
4Vw = 4000 - 4Va
Vw = 1000 - Va
When flying against the wind:
(Va-Vw)*(7 hours) = 4200 km
7Va - 7Vw = 4200
Substitute 1000-Va for Vw and solve for Va:
7Va - 7(1000-Va) = 4200
7Va -7000 + 7Va = 4200
14Va = 11200
Va = 800 km/hr
Rate of wind:
Vw = 1000 - Va = 1000 - 800 = 200 km/hour
help me with this question if you could
Answers
Determine the equation of the graph in its final position if the graph of y = 2X
is translated 2 units to the right and then 7 units upward.
1) y = 2x+7+ 2
2) y = 2X-2 + 7
3) y = 2X+2+7
O4) y = 2x-7, + 2
Answers
Answer:1
Step-by-step explanation:
Answer question 11 for me.
Answers
Answer:
what is true about p and q is that they both equal 20.
Step-by-step explanation:
[tex]\frac{2*20}{5*20}[/tex]=[tex]\frac{40}{100}[/tex]
hope this helps!
have a great day :)
5*20= 100
2* 20= 40
Also 2/5 = 40/100
What is the distance around a circle called?
A. Radius
B. Diameter
C. Circumference
D. Chord
Answers
Answer:
it is "c" (circumference)
Step-by-step explanation:
i hope this helps, have a good day
The distance around a circle called Circumference.
Option C is correct.
What is circumference?The circumference of any shape in mathematics defines the route or boundary that surrounds the shape. In other terms, the circumference is also known as the perimeter, and it aids in determining the length of any shape's contour. The perimeter and area of a circle are two important dimensions of a circle, as we all know.
The circumference of the circle, also known as the perimeter of the circle, is the measurement of the circle's boundary.
The area of a circle, on the other hand, defines the region it occupies.
If we open a circle and draw a straight line through it, the length of the line is the circumference.
As, The Circumference (or) perimeter of circle = 2πR
Thus, the distance around a circle called Circumference.
Learn more about Circumference here:
https://brainly.com/question/28757341
#SPJ7
What percent of a dollar is a nickel and a penny?
It is ______% of a dollar.
Answers
Answer:
6 %
Step-by-step explana
100 pennies makes a dollar... you just add 5 for the nickel and 1 fo the penny and it makes 6
PLS HELP
i said 45 but it was marked incorrect, im super confused
Answers
Answer:
60
Step-by-step explanation:
trangles always equal 180 degrees on the inside angles
180-75-45 = 60
Please helppp, worth 35!!!
Answers
Answer:
9.42
Step-by-step explanation:
Hey There!
The first step of this problem is to find the formula for arc length
[tex]arc-length=2\pi r(\frac{0}{360} )[/tex]
r=raduis
0 = angle
now we just plug in the values
[tex]arc-length=2\pi 10\frac{54}{360} \\2\pi =6.283185307\\6.283185307x10=62.83185307\\62.83185307\frac{54}{360}=9.424777961[/tex]
so the arc length equals 9.424777961
the last step is to round to the nearest hundreth
so your final answer is 9.42
The formula for the volume of a cone is V = 1/3 πr^2 h. Which part of the formula represents the area of the base?
Answers
Evaluate the following expression -5+(63/9)
Answers
Answer:
2
Step-by-step explanation:
Answer:
2
Step-by-step explanation:
A researcher wants to know how homeowners in her state feel about home warranties. She obtains a list of 879 homeowners in her state, selects 300 of them at random, and emails a questionnaire to them. 64 questionnaires are returned. Of these, 80% stated that they believe that the current home warranty coverage needs to be completely overhauled. Classify the following groups as the population or the sample for this particular study.
a. all homeowners in the researcher's state
b. The 879 homeowners whose names were obtained
c. The 64 homeowners who returned the questionnaire
d. The 80% who stated that the current home warranty coverage needs to be completely overhauled
Answers
Answer:
a. The population
b. The accessible population
c. The sample
d. The statistic
Step-by-step explanation:
a. All the homeowners in the researchers state = The target population
b. The 879 homeowners whose name were obtained = The sample frame (accessible population)
c. The 64 homeowners who returned the questionnaire = Research participants (the sample), the subjects
d. The 80% who stated that the current home warranty coverage needs to be completely overhauled = The statistic (subset or part of the sample)
i borrowed R3 000 from the bank . the contract stipulates that i have to repay the bank R3 900 after 2 years . how much much interest must i pay the bank per year
Answers
Answer:$450 per year
Step-by-step explanation: If you borrow 3000 dollars and after 2 years you have to pay 3,900 then after 2 years the intrest is 900 dollars, divide that by 2 for the two years and you get a yearly 450 dollars.
Carry out the following division.
Answers
Answer:
1: 8a²
2: 9a²b²c²
Step-by-step explanation:
1: 48a³ ÷ 6a
48÷6 = 8
8a²
2: 72a³b⁴c⁵ ÷ 8ab²c³
72÷ 8 =9
9a²b²c²
Sry , I could only solve the first one
Plz help ASAP 20 Points Determine the equation of circle A.
(x - 1)2 + (y + 2)2 = 9
(x + 1)2 + (y-2)2 = 9
(x-1)2 + (y + 2)2 = 3
(x + 1)2 + (y-2) = 3
Answers
Answer:
the answer is c
Step-by-step explanation:
your equation is to solve the circle so A could not be the answer B/c it can't be 9.the answer is c or d. But d can't give you 3 if you solve it. so the answer is C
7. Sketch the graph of f(x) = 2(x - 1.5)2 + 3, then state the domain and range of the function (show all your
work). (4 points)
8. Determine the value of a given that (7, 6) satisfies the quadratic function f(x) = a(x – 5)2 +6. (Show all your
work). (2 points)
Answers
9514 1404 393
Answer:
7. D: (-∞, ∞); R: [3, ∞); see attached for a graph (red)
8. a=0; see attached for a graph
Step-by-step explanation:
7. The function is a polynomial, so its domain is all real numbers.
The parabola opens upward. It has a minimum value of 3. The range is y ≥ 3.
__
8. Putting the given point coordinates in the equation, we can solve for a.
f(7) = 6
6 = a(7 -5)² +6
0 = a(2²)
0 = a
The value of a is zero.
(The given point has the same y-value as the vertex, but is not the vertex. The function can only go through that point if it is a horizontal line (not a parabola).) The attachment shows a graph.
In the function, g(x) = -2x, the independent variable has a value of 6. Find the value of the dependent variable. Type a
numerical answer in the space provided. Do not type spaces in your answer.
Answers
Answer:
g(6)
g(x)=-2x
g(6)=-2(6)
g(6)=-12
-12
that the answer
Step-by-step explanation:
[tex] \frac{47}{5} [/tex]
Kevin correctly answered 75% of 32 test questions. How many questions did Kevin answer correctly? How many more questions would Kevin have had to answer correctly to get more than 80% correct?
Answers
Answer:
At least 26 questions to get around an 82% not 25 because that equals 78%
Step-by-step explanation:
Answer:
Kevin answered 24 questions correctly.
Kevin would have to answer 25.6 questions correctly to get more than 80%.
A restaurant customer left 1.65 as a tip the tax was 7% and the tip was 15% of the after tax cost which information is not needed to compute the bill after tax and tip what was the total bill
A.the customer left 1.65 as a tip
B.the tax was 7%
C.the customer left a 15% tip
D.all of this information is needed to solve the problem
Answers
Answer:
D. All of this information is needed to solve the problem
Thank you
a line has a slope of -3 and a y-intercept of 5. write the equation of the line in slope-intercept form and explain how you would use the slope and y-intercept to graph the equation?
Answers
Answer:
y = -3x + 5
Step-by-step explanation:
Since the y-intercept occurs at the point (0,5), you can use that and the point slope equation to find the equation.
This looks like y - 5 = -3 (x - 0);
Solving for y, you get y = -3x + 5;
To graph this equation you would put one point at (0,5), then use the slope to count down three and to the left one to find other points, or you could just plug in numbers for x to find their corresponding y values and plot it like that.
Hopefully this helps- let me know if you have any questions!
PLEASE HELP MEEEEEEEEEEE
(2 questions)
(USA Test Prep and Quizzez)
Answers
Answer:
1. -25
2. 2.1
Step-by-step explanation:
-1/2(x + 5) = 10
divide both sides by 2.
-1(x + 5) = 20
-(x + 5) = 20
-x = 20 + 5
x = -25
k/3.5 + 7.4 = 8
2k/7 +37/5 = 8
10k = 280 - 259
10k = 21
k = 21/10 (2.1)
Answer:
1.x=15
2.k=2.1
Step-by-step explanation:
1.-1/2(x+5)=-10
-x+5/2=-10 multiply both sides by 2
-x-5=-10
-x=-20+5
-x=-15 multiply both sides by -1
x=15
2.k/3.5+7.4=8
k/3.5=8-7.4
k/3.5=0.6
multiply both sides by 3.5
k=2.1
21.8% all registered doctors are female if there were 51800 female doctors what is the total doctors that registered
Answers
Answer:
Step-by-step explanation:
21.8% of x = 51,800
0.218x =51,800
x= 51,800/0.218 = 237,615
The length of time the Sun is above the horizon is called the
Angle of insolation
Intensity of insolation
Duration of insolation
Longitude of insolation
Answers
help me on math pls plss I'm stuck agian:(((((
Answers
Answer:
the answer to a is 25, im unsure what B is.
Step-by-step explanation:
hope this helps!!!
The length of a photograph is 4 in. greater than its width. The area of the photograph is
52. in? What are the dimensions of the photograph?
Answers
Answer:
Step-by-step explanation:
The length of a photograph is 4 in. greater than its width. The area of the photograph is
52. in? What are the dimensions of the photograph?
please find the value of a
Answers
Answer:
I cant lp because
i'm on the school computer so sorry. <:(
so I cant see your Step-by-step explanation:
WILL MARK BRANL:IEST NO FAKE ANSWERS I NEED ASAP
Answers
Answer:
(-5, 9)
Step-by-step explanation: