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 !
for the function f(x)=5 evaluate and simplify the expression: f (a+h)-f(a)/h
Answer:
0 is the answer assuming the whole thing is a fraction where the numerator is f(a+h)-f(a) and the denominator is h.
Step-by-step explanation:
If the expression for f is really a constant, then the difference quotient will lead to an answer of 0.
If the extra for f is linear (including constant expressions), the difference quotient will be the slope of the expression.
However, let's go about it long way for fun.
If f(x)=5, then f(a)=5.
If f(x)=5, then f(a+h)=5.
If f(a)=5 and f(a+h)=5, then f(a+h)-f(a)=0.
If f(a+h)-f(a)=0, then [f(a+h)-f(a)]/h=0/h=0.
Which function has no horizontal asymptote?
Answer:
[tex]{ \tt{f(x) = \frac{x - 1}{3x} }}[/tex]
Answer:
c
Step-by-step explanation:
edge
The 2010 GSS provides the following statistics for the average years of education for lower-, working-, middle-, and upper-class respondents and their associated standard deviations. Assume that years of education are normally distributed in the population. Mean Standard Deviation N Lower-class 11.61 2.67 123 Working-class 12.80 2.85 697 Middle-class 14.45 3.08 626 Upper-class 15.45 2.98 38 How many years of education correspond to a Z score of +1.2 for upper-class respondents?
Answer:
The answer is "18.087 years".
Step-by-step explanation:
For upper class:
[tex]\mu=15.45 \ years\\\\\alpha=2.98 \ years\\\\[/tex]
[tex]P(Z \leq 1.2)[/tex] from the standard normal distribution on the table:
[tex]P(Z \leq 1.2) =0.8849\\\\x=z_{\alpha}+\mu\\\\[/tex]
[tex]=0.8849 \times 2.98 +15.45\\\\ = 2.637002+15.45 \\\\=18.087 \ \ years\\[/tex]
Mathematics I need help
Answer:
B
Step-by-step explanation:
Exclude C:
[tex] |x| [/tex]
is not curved
To shift right, minus inside the
[tex] |?| [/tex]
Thus
[tex] |x - 4| [/tex]
To shift up, add outside the
[tex] |?| [/tex]
Thus:
[tex] |x +4| + 2[/tex]
B
Brainliest please~
a pie chart is divided into four sectors in fig. 12.42. Each sector represents a percentage of the whole. The two larger sectors are equal and each represents x%. What is the angle subtended by one of those larger sectors ?
Answer:
Angle formed by the sector measuring x% will be 126°.
Step-by-step explanation:
Since, sum of all sectors formed in a circle is 100%.
By adding the measures of all the sectors,
x + x + 21 + 9 = 100
2x + 30 = 100
2x = 70
x = 35%
Now we know sum of all the central angles formed at the center of a circle = 360°
Therefore, angle formed by x% = 360° × 35%
= [tex]\frac{360\times 35}{100}[/tex]
= 126°
How do I find the missing number?
Answer:
to find the missing number is all u have to do is understand the problem and silve the problem!
Step-by-step explanation:
paki brainly po
Which of the following values cannot be probabilities? 3/5, 2, 0, 1, −0.45, 1.44, 0.05, 5/3 Select all the values that cannot be probabilities.
Given:
The numbers are [tex]\dfrac{3}{5},2,0,1,-0.45, 1.44[/tex].
To find:
All the values that cannot be probabilities.
Solution:
We know that,
[tex]\text{Probability}=\dfrac{\text{Favorable outcomes}}{\text{Total outcomes}}[/tex]
The minimum value of favorable outcomes is 0 and the maximum value is equal to the total outcomes. So, the value of probability lies between 0 and 1, inclusive. It other words, the probability lies in the interval [0,1].
[tex]0\leq \text{Probability}\leq 1[/tex]
From the given values only [tex]\dfrac{3}{5}, 0, 1[/tex] lie in the interval [0,1]. So, these values can be probabilities.
The values [tex]2,-0.45, 1.44[/tex] does not lie in the interval [0,1]. So, these values cannot be probabilities.
Therefore, the correct values are [tex]2,-0.45, 1.44[/tex].
The force F (in pounds) needed on a wrench handle to loosen a certain bolt varies inversely with the length L (in inches) of the handle. A force of 40 pounds is needed when the handle is 7 inches long. If a person needs 20 pounds of force to loosen the bolt, estimate the length of the wrench handle. Round answer to two decimal places if necessary.
in inches
Answer:
14 inches
Step-by-step explanation:
Since F is inversely proportional to L,
[tex]f = \frac{k}{l} \\ when \: f = 40 \: l \: = 7 \\ \frac{k}{7} = 40 \\ k = 280 \\ when \: f = 20 \\ 20 = \frac{280}{l} \\ l = 14[/tex]
) dy 2x
------ = ---------------
dx yx2 + y
Step-by-step explanation:
[tex]\dfrac{dy}{dx} = \dfrac{2x}{y(x^2 + 1)}[/tex]
Rearranging the terms, we get
[tex]ydy = \dfrac{2xdx}{x^2 + 1}[/tex]
We then integrate the expression above to get
[tex]\displaystyle \int ydy = \int \dfrac{2xdx}{x^2 + 1}[/tex]
[tex]\displaystyle \frac{1}{2}y^2 = \ln |x^2 +1| + k[/tex]
or
[tex]y = \sqrt{2\ln |x^2 + 1|} + k[/tex]
where I is the constant of integration.
solve the following system of equations with the help of matrix ::. x-2y-4=0 & -3x+5y+7=0
Answer:
(x, y) = (-34,-19)
Step-by-step explanation:
...................................................
Prove this plzzz help me
Answer:
Answer is in the picture. have a look
Use the coordinates of the labeled point to find a point-slope equation of the
line.
5
5
(-2,-5) 6.5
>
O A. y- 5 = -2(x - 2)
O B. y + 5 = 2(x + 2)
O C. y + 5 = -2(x + 2)
OD. y- 5 = 2(x - 2)
Answer:
B. [tex] y + 5 = 2(x + 2) [/tex]
Step-by-step explanation:
Point-slope equation is given as [tex] y - b = m(x - a) [/tex], where,
(a, b) = (-2, -5)
[tex] m = slope = \frac{y_2 - y_1}{x_2 - x_1} [/tex]
Using two points on the line (-2, -5) and (0, -1),
Slope (m) = (-1 -(-5))/(0 -(-2)) = 4/2
m = 2
✔️To write the equation in point-slope form, substitute a = -2, b = -5, and m = 2 into [tex] y - b = m(x - a) [/tex]
Thus:
[tex] y - (-5) = 2(x - (-2)) [/tex]
[tex] y + 5 = 2(x + 2) [/tex]
Factor 2x2+25x+50. Rewrite the trinomial with the x-term expanded, using the two factors.
9514 1404 393
Answer:
rewrite: 2x^2 +5x +20x +50factored: (x +10)(2x +5)Step-by-step explanation:
I find this approach the most straightforward of the various ways that trinomial factoring is explained or diagramed.
You want two factors of "ac" that have a total of "b". Here, that means you want factors of 2·50 = 100 that have a total of 25. It is helpful to know your times tables.
100 = 1·100 = 2·50 = 4·25 = 5·20 = 10·10
The sums of these factor pairs are 101, 52, 29, 25, and 20. We want the pair with a sum of 25, so that's 5 and 20.
The trinomial can be rewritten using these factors as ...
2x^2 +5x +20x +50
Then it can be factored by grouping consecutive pairs:
(2x^2 +5x) +(20x +50) = x(2x +5) +10(2x +5) = (x +10)(2x +5)
_____
Additional comment
It doesn't matter which of the factors of the pair you write first. If our rewrite were ...
2x^2 +20x +5x +50
Then the grouping and factoring would be (2x^2 +20x) +(5x +50)
= 2x(x +10) +5(x +10) = (2x +5)(x +10) . . . . . same factoring
g At a certain gas station, 30% of all customers use the restroom. What is the probability that, out of the next 10 customers, (a) exactly 4 will use the restroom
Answer:
[tex]P(x=4) = 0.200[/tex]
Step-by-step explanation:
Given
[tex]n=10[/tex] --- selected customers
[tex]x = 4[/tex] --- those that are expected to use the restroom
[tex]p =30\% = 0.30[/tex] --- proportion that uses the restroom
Required
[tex]P(x = 4)[/tex]
The question illustrates binomial probability and the formula is:
[tex]P(x) = ^nC_x * p^x * (1 - p)^{n - x}[/tex]
So, we have:
[tex]P(x=4) = ^{10}C_4 * (0.30)^4 * (1 - 0.30)^{10 - 4}[/tex]
[tex]P(x=4) = ^{10}C_4 * (0.30)^4 * (0.70)^6[/tex]
[tex]P(x=4) = 210* (0.30)^4 * (0.70)^6[/tex]
[tex]P(x=4) = 0.200[/tex]
At the 6th grade school dance, there are 132 boys, 89 girls, and 14 adults. What is the ratio of adults to boys at the school dance?
Answer:
14 to 132
Step-by-step explanation:
We are given that there are 132 boys and 14 adults. Since the question is only asking for the ratio of adults to boys, we don't have to worry about the number of girls in this question. From here, we see that the question is asking for the ratio of adults to boys, so we put it in that exact order. Our answer is 14 to 132. I hope this helps and please don't hesitate to reach out with more questions!
An economic instructor at UCF is interested in the relationship between hours spent studying and total points earned in a course. Data collected on 11 students who took the course last semester follow:
# of observation(s) n = 30
# of independent variable(s) = 1
SSR = 1,297 SSE= 920
Required:
Find the F test statistic.
Answer:
[tex]F = 39.47[/tex]
Step-by-step explanation:
Given
[tex]n = 30[/tex] --- observations
[tex]p = 1[/tex] -- variables
[tex]SSR = 1,297[/tex]
[tex]SSE= 920[/tex]
Required
The F statistic
This is calculated using:
[tex]F = \frac{SSR}{p} \div \frac{SSE}{n - p -1}[/tex]
[tex]F = \frac{1297}{1} \div \frac{920}{30 - 1 -1}[/tex]
[tex]F = \frac{1297}{1} \div \frac{920}{28}[/tex]
[tex]F = 1297 \div \frac{920}{28}[/tex]
Rewrite as:
[tex]F = 1297 * \frac{28}{920}[/tex]
[tex]F = \frac{1297 *28}{920}[/tex]
[tex]F = \frac{36316}{920}[/tex]
[tex]F = 39.47[/tex]
the complement of guessing 5 correct answers on a 5 question true or false examination is
Answer:
Guessing at least one incorrect answer
Step-by-step explanation:
The complement of guessing 5 correct answers on a 5-question true/false exam is-
Guessing at least one incorrect answer because, when 1 or more questions are incorrectly guessed, the event of 5 correct answers can not occur.
what is answer if 2xyx5
Answer:
Answer is 3bu2(DeEZ)=1
Step-by-step explanation:
Sarah ordered 39 shirts that cost $8 each. She can sell each shirt for $16.19. She sold 32 shirts to customers. She had to return 7 shirts and pay a $1.4 charge for each returned shirt. Find Sarah's profit.
Answer:
$196.28
Step-by-step explanation:
Original cost: 39 × $8 = $312
Revenue: 32 × $16.19 = $518.08
Return charge: 7 × $1.4 = $9.8
$312 + $9.8 = total cost, which is $321.8
$518.08 - $321.8 = profit
Profit = $196.28
The dress store is having a sale where all merchandise is 1/4 off. A woman buys $48 of merchandise at a sale price.
Answer:$36 depending on what question is i just assuming how much she has to pay
Step-by-step explanation:
48 divded by 4 is 12. $48-$12 is $36. The $12 is the 1/4 discount.
A certain list of movies were chosen from lists of recent Academy Award Best Picture winners, highest grossing movies, series movies (e.g. the Harry Potter series, the Spiderman series), and from the Sundance Film Festival and are being analyzed. The mean box office gross was $138.64 million with a standard deviation of $11.2526 million. Given this information, 98.49% of movies grossed greater than how much money (in millions)
Please help asap I needs someone to find the addition property added
A
Step-by-step explanation:
you can notice that at step 2 9 is added on both sides that is the addition property of equality
A paddleboat can move at a speed of 4 km/h in still water. The boat is paddled 12 km downstream in a river in the same time it takes to go 6 km upstream. What is the speed of the river?
Answer:
Speed of the river = [tex]\frac{4}{3}[/tex] km per hour
Step-by-step explanation:
Speed of the boat in still water = 4 km per hour
Let the speed of the river = v km per hour
Speed of the boat upstream = (4 - v) km per hour
Time taken to cover 6 km = [tex]\frac{\text{Distance}}{\text{Speed}}[/tex]
= [tex]\frac{6}{4-v}[/tex] hours
Speed of the boat downstream = (4 + v) km per hour
Time taken to cover 12 km = [tex]\frac{12}{4+v}[/tex] hours
Since, time taken by the boat in both the cases is same,
[tex]\frac{6}{4-v}= \frac{12}{4+v}[/tex]
6(4 + v) = 12(4 - v)
24 + 6v = 48 - 12v
12v + 6v = 48 - 24
18v = 24
v = [tex]\frac{24}{18}[/tex]
v = [tex]\frac{4}{3}[/tex] km per hour
it's tooooo easy who wants brain list
Answer:
1) Isosceles
2) Acute
3) Right angled
4( Obtuse
5) Equilateral
The area of a rectangle is 110 square units. Its length measures 11 units. Find the
length of its diagonal. Round to the nearest tenth of a unit.
Answer:
A
=
w
l
d
=
w
2
+
l
2
Solving for
d
d
=
l
2
+
(
A
l
)
2
=
11
2
+
(
110
11
)
2
≈
14.86607
The length of the diagonal of the rectangle is 14.9 units.
What is a diagonal?A diagonal is the longest line that divides a plane shape into two halves.
To calculate the diagonal of the rectangle, we use Pythagoras theorem.
Formula:
A = lw.............. Equation 1Where:
A = Area of the rectanglel = Length of the rectanglew = width of the rectangle.make w the subject of the equation
w = A/l.............. Equation 2From the question,
Given:
A = 110 square unitsl = 11 unitsSubstitute these values into equation 2
w = 110/11w = 10 units.Finally, to calculate the diagonal of the rectangle, we use the formula below
d² = l²+w²............. Equation 3Given:
w = 10 unitsl = 11 units.Substitute these values into equation 3
d² = 10²+11²d² = 100+121d² = 221d = √221d = 14.9 units.Hence, the length of the diagonal of the rectangle is 14.9 units.
Learn more about diagonal here: https://brainly.com/question/654982
#SPJ2
If h(x) is the parent function, which equation describes the function song shifted 3 units left and 5 units down?
Answer:
h(x + 3) - 5Step-by-step explanation:
Given function h(x).
Shift left:
h(x) → h(x + 3)Shift down:
h(x + 3) → h(x + 3) - 5Given function is,
→ h(x)
As we shift left,
→ h(x) = h(x + 3)
As we shift down,
→ h(x + 3) = h(x+3)-5
Then the equation is,
→ h(x+3)-5
It is correct answer.
please show me step by step how to simplify this equation
Answer:
1-x^2/x^3 - 1 = 1/x
Step-by-step explanation:
First rewrite x^3 as x^2 * x cancel x^2 in both numerator and denominator.
Write below
1 - 1/x - 1
Subtract
1 - 1 = 0
now simplify
1 -1 /x - 1 = 1/x
1/x = Answer
Can you Understand
Sam wants to build a unique pyramid bookend for his study. It's an oblique pyramid
with a right triangular base. The sides of the base are 3, 4, and 5 inches long. The
pyramid will fit exactly inside his bookshelf, which has a height of 18 inches. He
wishes to build the pyramid out of modeling clay. How many cubic inches of clay
does Sam need to buy?
36in^3
24in^3
62.8in^3
216in^3
Answer:
Volume of triangular pyramid = 36 inch³
Step-by-step explanation:
Given:
Sides of base triangle = 3, 4, 5 inches
Height of model = 18 inches
Find:
Volume of triangular pyramid
Computation:
Given base triangle is a right angle triangle
So,
Area of base = (1/2)(b)(h)
Area of base = (1/2)(3)(4)
Area of base = (1/2))(12)
Area of base = 6 inch²
Volume of triangular pyramid = (1/3)(Area of base)(Height of model)
Volume of triangular pyramid = (1/3)(6)(18)
Volume of triangular pyramid = 36 inch³
the diagram shows a regular dodecagon. a) work out the size of one interior angle. b) work out the size of one exterior angle.
Answer: Interior angle: 150 degrees Exterior angle: 30 degrees
Step-by-step explanation:
We use the angle formula to find the value of an interior angle: 180*(12-2)/12 = 150 degrees. Since an exterior angle is the supplement of an interior angle, the measure of an exterior angle is 180 - 150 = 30 degrees
A party supply company makes cone shaped party hats for children using thin cardboard. To the nearest square centimeter, how much cardboard is required to make the party hate use pie = 3.14.
Answer:
A. 754 cm²
Step-by-step explanation:
Amount of cardboard needed = surface area of the cone
Curved surface area of the cone = πrl
Where,
π = 3.14
r = ½(20) = 10 cm
l = 24 cm
Plug in the values into the formula
Curved surface area = 3.14 × 10 × 24 = 753.6 ≈ 754 cm²
