To prove that: (2cosA+1) (2cosA-1) = 2cos2A+1
We try to solve one side of the equation to get the other side of the equation.
In this case, we'll solve the right hand side (2cos2A + 1) of the equation with the aim of getting the left hand side of the equation (2cosA + 1)(2cosA - 1)
Solving the right hand side: 2cos2A + 1
i. We know that cos2A = cos(A+A) = cosAcosA - sinAsinA
Therefore;
cos2A = cos²A - sin²A
ii. We also know that: cos²A + sin²A = 1
Therefore;
sin²A = 1 - cos²A
iii. Now re-write the right hand side by substituting the value of cos2A as follows;
2cos2A + 1 = 2(cos²A - sin²A) + 1
iv. Expand the result in (iii)
2cos2A + 1 = 2cos²A - 2sin²A + 1
v. Now substitute the value of sin²A in (ii) into the result in (iv)
2cos2A + 1 = 2cos²A - 2(1 - cos²A) + 1
vi. Solve the result in (v)
2cos2A + 1 = 2cos²A - 2 + 2cos²A + 1
2cos2A + 1 = 4cos²A - 2 + 1
2cos2A + 1 = 4cos²A - 1
2cos2A + 1 = (2cosA)² - 1²
vii. Remember that the difference of the square of two numbers is the product of the sum and difference of the two numbers. i.e
a² - b² = (a+b)(a-b)
This means that if we put a = 2cosA and b = 1, the result from (vi) can be re-written as;
2cos2A + 1 = (2cosA)² - 1²
2cos2A + 1 = (2cosA + 1)(2cosA - 1)
Since, we have been able to arrive at the left hand side of the given equation, then we can conclude that;
(2cosA + 1)(2cosA - 1) = 2cos2A + 1
Answer:
[tex]\boxed{\sf LHS = RHS }[/tex]
Step-by-step explanation:
We need to prove that ,
[tex]\sf\implies (2 cosA +1)(2cosA-1) = 2cos2A+1[/tex]
We can start by taking RHS and will try to obtain the LHS . The RHS is ,
[tex]\sf\implies RHS= 2cos2A + 1 [/tex]
We know that , cos2A = 2cos²A - 1 ,
[tex]\sf\implies RHS= 2(2cos^2-1)-1 [/tex]
Simplify the bracket ,
[tex]\sf\implies RHS= 4cos^2A - 2 +1 [/tex]
Add the constants ,
[tex]\sf\implies RHS= 4cos^2-1 [/tex]
Write each term in form of square of a number ,
[tex]\sf\implies RHS= (2cos^2A)^2-1^2 [/tex]
Using (a+b)(a-b) = a² - b² , we have ,
[tex]\sf\implies RHS= (2cosA+1)(2cosA-1) [/tex]
This equals to LHS , therefore ,
[tex]\sf\implies \boxed{\pink{\textsf{\textbf{ RHS= LHS }}}} [/tex]
Hence Proved !
what is the distance in the image below?
The distance is:
5 + 3 = 8 units
Since the segment is completely horizontal we need not to use formula for computing the length of a segment in 2D euclidean space.
Instead we can simplify the problem to a single dimension, only considering the x-coordinates of the endpoints of the segment.
The x-coordinates are -5 and 3.
Subtracting and applying absolute value yields the answer,
[tex]\mathrm{abs}(-5-3)=\boxed{8}[/tex].
Hope this helps.
The x-value(s) for which f(x)g(x) is/are ___
9514 1404 393
Answer:
x = -1, 1, 9
Step-by-step explanation:
You want x such that f(x) = g(x). Subtracting g(x) from both sides of this equation lets us rewrite it as ...
f(x) -g(x) = 0
x³ -9x² -(x -9) = 0
x²(x -9) -1(x -9) = 0 . . . factor the first pair of terms
(x² -1)(x -9) = 0 . . . . . . use the distributive property
(x -1)(x +1)(x -9) = 0 . . . . factor the difference of squares
Values of x that make these factors zero will make f(x) = g(x):
x = -1, 1, 9 for f(x) = g(x)
Two linear equations are shown in the graph.
#Brainliest award
What are the coordinates of the point where the two lines intersect?
A. (–2, 3)
B. (3, 3)
C. (3, 0)
D. (–3, 3)
Answer:
I am taking this graph because this question looked similar to this one.
Step-by-step explanation:
Answer should be B.
The intersection point is (3,3)
A sociologist claims the probability that a person picked at random in Times Square in New York City is visiting the area is 0.83. You want to test to see if the claim is correct. State the null and alternative hypotheses.
Answer:
The answer is:
[tex]H_0: p=0.83\\\\H_a: p \neq 0.83[/tex]
Step-by-step explanation:
Now, we're going to test if sociologists claim to be have visited a region of 0.83 by a person picked randomly on Time In New York City.
Therefore, null or other hypotheses are:
[tex]H_0: p=0.83\\\\H_a: p \neq 0.83[/tex]
12x + 1 - 2(y + 2) = 12x - ______ - 2y
Answer:
-3
Step-by-step explanation:
12x + 1 - 2(y + 2)
=> 12x + 1 - 2y - 4
=> 12x - 3 - 2y
Answer:
-3
Step-by-step explanation:
12x+1-2y-4
12x+1-2y-4
12x-2y-3
One way to check on how representative a survey is of the population from which it was drawn is to compare various characteristics of the sample with the population characteristics. A typical variable used for this purpose is age. The 2010 GSS of the American adult population found a mean age 49.28 years and a standard deviation of 17.21 for its sample of 4,857 adults. Assume that we know from Census data that the mean age of all American adults is 37.2 years.
Required:
a. State the research and the null hypothesis setting for a two-tailed test.
b. Calculate the t statistics and test the null hypothesis setting alpha at .01. What did you find?
c. What is your decision about the null hypothesis? What does this tell us about how representative the sample is of the American adult population?
Answer:
a) See step by Step explanation
b) z(s) = 48.88
c) We reject H₀. The sample is not representative of American Adult Population
Step-by-step explanation:
From sample
sample mean . x = 49.28
sample standard deviationn s = 17.21
sample size n₁ = 4857
Population mean according to Census data
μ = 37.2
a) Test Hypothesis
Null Hypothesis . H₀ . x = μ = 37.2
Alternative Hypothesis Hₐ . x ≠ μ
b) We have sample size (4857) we can use normal distribution
z (c) for α = 0.01 α/2 . = 0.005 is from z-table . z(c) = 2.575
To calculate z(s) = ( x - μ ) / s /√n
z(s) = 12.08 * √4857 / 17.21
z(s) = 12.08* 69.64 / 17.21
z(s) = 48.88
z(s) > z(c)
We should reject H₀. The sample is not representative of American Adult population
21. Which of the following statements is true?
(1) -18 > -5
(2) -5 > -0.5
(3) -5> 0
(4) -5 > 52
(5) -5 > -18
Answer: (5) -5 > -18
Step-by-step explanation:
The farther the negative number is from 0, the smaller it becomes.Negative numbers will be smaller than positive numbers, since they're smaller than 0.-5 is 5 away from zero, making it larger than -18 since it's closer to 0, while -18 is 18 away from zero.
Area of composite shapes ?
Answer: 58
Step-by-step explanation: you add them all together
Its 108 the other answer is the perimeter not the area.
BRAINLIEST HELP ME!!!
Which graph shows the solution to this system of linear Inequalities?
ys2x-3
A. Graph
B. Graph B
C. Graph A
D. Graph D
A trough is 10 ft long and its ends have the shape of isosceles triangles that are 4 ft across at the top and have a height of 1 ft. If the trough is being filled with water at a rate of 15 ft3/min, how fast is the water level rising when the water is 8 inches deep
Answer:
7.5 ft³/min
Step-by-step explanation:
Let x be the depth below the surface of the water. The height, h of the water is thus h = 10 - x.
Now, the volume of water V = Ah where A = area of isosceles base of trough = 1/2bh' where b = base of triangle = 4 ft and h' = height of triangle = 1 ft. So, A = 1/2 × 4 ft × 1 ft = 2 ft²
So, V = Ah = 2h = 2(10 - x)
The rate of change of volume is thus
dV/dt = d[2(10 - x)]/dt = -2dx/dt
Since dV/dt = 15 ft³/min,
dx/dt = -(dV/dt)/2 = -15 ft³/min ÷ 2 = -7.5 ft³/min
Since the height of the water is h = 10 - x, the rate at which the water level is rising is dh/dt = d[10 - x]/dt
= -dx/dt
= -(-7.5 ft³/min)
= 7.5 ft³/min
And the height at this point when x = 8 inches = 8 in × 1 ft/12 in = 0.67 ft is h = (10 - 0.67) ft = 9.33 ft
Please hlep x^2+6x+1=0
Answer:
Substitute into the quadratic formula
-6 ± √32 / 2
= -3 ± √16
= 1 and -1 are the answer
Answer:
x = - 3 ± 2[tex]\sqrt{2}[/tex]
Step-by-step explanation:
Given
x² + 6x + 1 = 0 ( subtract 1 from both sides )
x² + 6x = - 1
Using the method of completing the square
add/ subtract ( half the coefficient of the x- term)² to both sides
x² + 2(3)x + 9 = - 1 + 9
(x + 3)² = 8 ( take the square root of both sides )
x + 3 = ± [tex]\sqrt{8}[/tex] = ± 2[tex]\sqrt{2}[/tex] ( subtract 3 from both sides )
x = - 3 ± 2[tex]\sqrt{2}[/tex]
Then
x = - 3 - 2[tex]\sqrt{2}[/tex] , x = - 3 + 2[tex]\sqrt{2}[/tex]
3x7 I need help with this i do not know the answer pls help.
Answer:
21
Step-by-step explanation:
7+7+7=21
Two functions, A and B, are described as follows: Function A y = 9x + 4 Function B The rate of change is 3 and the y-intercept is 4. How much more is the rate of change of function A than the rate of change of function B?
2
3
6
9
Answer:
[tex]{ \tt{rate \: of \: change \: in \: A = 9}}[/tex]
Rate of change in function A is two times than that in function B
What is the mean?
9.12.34.6.8.9.
Answer:
13
Step-by-step explanation:
The mean is the average of the numbers. It is easy to calculate: add up all the numbers, then divide by how many numbers there are. In other words it is the sum divided by the count.
Answer:
The mean (average) of these numbers is equal to 13.
Step-by-step explanation:
Another word for the "mean" of numbers is the "average" of numbers. You can find the average by adding all the numbers together and then dividing the sum you got by the number of values you added together, so in our case, there are 6 values given, therefore we will find the sum of all these numbers and then divide it by 6...
[tex]\frac{9 + 12 + 34 + 6 + 8 + 9}{6} = \frac{78}{6} = 13[/tex]
Therefore, the mean (average) of this number is equal to 13.
factor the GCF out of the polynomial
Answer:
1. Find the GCF of all the terms in the polynomial.
2. Express each term as a product of the GCF and another factor.
3. Use the distributive property to factor out the GCF.
The graphs below have the same shape the equation of the bluegrass is f(x)=x^3 what is the equation of the red graph
Answer:
g(x) = x^3 - 2
Step-by-step explanation:
As you can see on the graph, the line has been translated down 2 units.
If the graph of f has the same shape as the graph of g, then the slope remains the same. The y intercept (k) changes by -2 units, so the k value is -2
g(x) = x^3 - 2
Hope this helps!!
A Line passes through the .4 -6 and has a slope of -3 and four which is the equation of the line
Answer:
(in the image)
Step-by-step explanation:
I'm not sure I understood your question completely but I hope this helps.
The length of a rectangle is six times it’s width. If the area of the rectangle is 486 cm^2, find the perimeter.
Answer:
54 cm is the perimeter I think
if f(x)=x+8 and g(x)=-4x-3 find (f+g)(x)
Answer:
for this case we have the following functions:
f (x) = x + 8
g (x) = -4x - 3
Subtracting the functions we have:
(f - g) (x) = f (x) - g (x)
(f - g) (x) = (x + 8) - (-4x - 3)
Rewriting:
(f - g) (x) = x + 8 + 4x + 3
(f - g) (x) = 5x + 11
Answer:
D. (f - g) (x) = 5x + 11
Two positive integers are 3 units apart on a number line. Their product is 108.
Which equation can be used to solve for m, the greater integer?
m(m – 3) = 108
m(m + 3) = 108
(m + 3)(m – 3) = 108
(m – 12)(m – 9) = 108
Answer:
m(m – 3) = 108
The correct equation can be used to solve for m, the greater integer is,
⇒ m (m - 3) = 108
We have to given that,
Two positive integers are 3 units apart on a number line.
And, Their product is 108.
Let us assume that,
In a number line, first point is m
Then, Second point is, m - 3
So, We get;
The correct equation can be used to solve for m, the greater integer is,
⇒ m (m - 3) = 108
Learn more about the equation visit:
brainly.com/question/28871326
#SPJ7
I need to find a but I don’t know how to, could you please explain
Answer:
87
Step-by-step explanation:
Given is a figure of cyclic quadrilateral.
Opposite angles of a cyclic quadrilateral are supplementary.
Therefore,
z° + 93° = 180°
z° = 180° - 93°
z° = 87°
z = 87
2. What facts are needed to solve the problem?
Answer:
firstly we have to identify the problems, understand carefully and chose the best way to solve problems.
Sita and Ram divided Rs. 250 into 2:3 ratio. Find their shares.
Answer:
Rs. 100 and Rs. 150
Step-by-step explanation:
the ratio = 2:3 => the sum = 2+3=5
Sita gets = 2/5 × 250 = 100
Ram gets = 3/5 × 250 = 150
Find the mean of 2,2,2,2 and 2
Answer:
2
Step-by-step explanation:
mean = sum of data / no of data
=2+2+2+2+2/5
=10/5
=2
HELPPP PLEASEEE! I tried everything from adding to dividing, subtracting, multiplying but still no correct answer. Can someone help me out here please? I am not sure where to start either now. Thank you for your time.
Find the area of the regular pentagon. 4.1 cm 6 cm Area = [?] cm? Enter your answer to the nearest tenth.
Answer:
Area of the given regular pentagon is 61.5 cm².
Step-by-step explanation:
Area of a regular polygon is given by,
Area = [tex]\frac{1}{2}aP[/tex]
Here, a = Apothem of the polygon
P = Perimeter of the polygon
Apothem of the regular pentagon given as 4.1 cm.
Side of the pentagon = 6 cm
Perimeter of the pentagon = 5(6)
= 30 cm
Substituting these values in the formula,
Area = [tex]\frac{1}{2}(4.1)(30)[/tex]
= 61.5 cm²
Therefore, area of the given regular pentagon is 61.5 cm².
Let f(x)
2x + 8, g(x) = x2 + 2x – 8, and h(x) = 3x – 6.
Perform the indicated operation. (Simplify as far as possible.)
(h · f)(3) =
Answer:
36
Step-by-step explanation:
(h · f)(x) = h(f(x))
h(f(x)) = h(2x+8)
h(f(x))= 3(2x+8) - 6
h(f(x)) = 6x + 24 - 6
h(f(x))= 6x + 18
If x = 3
h(f(x))= 6(3) + 18
h(f(x))= 18 + 18
h(f(x))= 36
Hence (h · f)(3) = 36
Which value of X makes the quotient of (5x^5+90x^2-135x)/(x+3) undefined
A -2
B -3
C -4
D -1
Answer:
b) - 3
Step-by-step explanation:
If x = -3 , then
x + 3 = -3 + 3 = 0
So, denominator would become 0. So , anything divided by 0 is undefined
The mean per capita consumption of milk per year is 131 liters with a variance of 841. If a sample of 132 people is randomly selected, what is the probability that the sample mean would be less than 133.5 liters
Answer:
0.8389 = 83.89% probability that the sample mean would be less than 133.5 liters.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
The mean per capita consumption of milk per year is 131 liters with a variance of 841.
This means that [tex]\mu = 131, \sigma = \sqrt{841} = 29[/tex]
Sample of 132 people
This means that [tex]n = 132, s = \frac{29}{\sqrt{132}}[/tex]
What is the probability that the sample mean would be less than 133.5 liters?
This is the p-value of Z when X = 133.5. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{133.5 - 131}{\frac{29}{\sqrt{132}}}[/tex]
[tex]Z = 0.99[/tex]
[tex]Z = 0.99[/tex] has a p-value of 0.8389
0.8389 = 83.89% probability that the sample mean would be less than 133.5 liters.
Sorry to ask so many questions but I need help in MATH
PLZZZ HELPPP
Answer:
24 26 27 94 is the answer 45
Answer:
the correct answer is 45