Review the proof of Cosine (StartFraction theta Over 2 EndFraction) = plus-or-minus StartRoot StartFraction 1 + cosine theta Over 2 EndFraction EndRoot.
Which step contains an error?
Answers
Answer:
Error in step (5)
Step-by-step explanation:
Steps Statements
1 cos(2x) = 2cosx - 1
2 Let (2x) = θ
3 Then x = [tex]\frac{\theta }{2}[/tex]
4 cos(θ) = [tex]2\text{cos}^2{\theta}-1[/tex]
5 cos(θ) + 1 = [tex]2\text{cos}^2{\frac{\theta}{2}}[/tex]
6 [tex]\frac{1+\text{cos}\theta }{2}=cos^{2}\frac{\theta }{2}[/tex]
7 [tex]\text{cos}^{2}\frac{\theta }{2}=\frac{1+\text{cos}\theta }{2}[/tex]
8 [tex]\text{cos}(\frac{\theta }{2})=\pm \sqrt{\frac{1+cos(\theta)}{2} }[/tex]
By comparing the solution given in the picture attached with the solution above,
Step 5 has error.
There should be [cos(θ) + 1 = [tex]2\text{cos}^2({\frac{\theta}{2}})[/tex]] in place of [-1 + cos(θ) = [tex]2\text{cos}^2({\frac{\theta}{2}})[/tex]]
Answer:
C. Step five
Step-by-step explanation:
got it right on edge :)
Related Questions
Which graph shows a set of ordered pairs that represent a function?
Answers
Answer:
Step-by-step explanation:
Its either a or b
solve the equality 7-6x < 19
Answers
Answer:
x>-2
Step-by-step explanation:
Answer:
7-6x < 19
-6x< 19 - 7
-6x < 12
x < -2
Can someone please help me ?
Answers
Answer:
D
Step-by-step explanation:
Since it is 28 meters deep, it would be -28. And it increases 0.012 meters per minute, and time is t, so that would be 0.012t. So the equation is 0.012t - 28 = 30.
HELP AND GET BRAINLY 20 PTS
Answers
Answer:
4
Step-by-step explanation:
it crosses at 4
Answer:
C. 4
Step-by-step explanation:
The Y-intercept of a line is where the line intersects with the y-axis, it is also when x=0. To find the intercept simply go along the axis until you run into the line, in this case, you hit the line when y=4. If the intercept is not shown on the graph you can use the slope-point equation and then simplify for the intercept.
Can I get an answer ASAP? Mark you as the brainiest
(b + –2) + 2
Answers
3 points
Kim and Glen were selling candy bars while working through a company. In order to sell with this company, they required you to wear their uniform which had an
upfront cost of 10 dollars. The profit made from selling each candy bar was 2 dollars.
Kim said she could represent her total profit with the expression 20-10, wherec is the amount of candybars sold.
Glen said he could represent his total profit with the expression 2c+10, where cis by the amount of candybars sold.
Who do you think has come up with correct expression? What mistake did Kim or Glen make and how could they fox it?
Please help will make Brainlest
Answers
Answer:
Kim made the mistake
Step-by-step explanation:
She should take away the 0 in 20
Given mn, find the value of x.
(x+14)
(9x-4)
Answers
Answer:
Step-by-step explanation:
espera y termino y te ayudo vale que me falta poco
3. A random survey of the quality of Raleigh city parks is taken. Sixty-five percent of the people surveyed were pleased with the condition of the parks. If 280 people were surveyed, then how many were pleased?
Answers
Answer: 182 people
Step-by-step explanation:
The following can be deduced from the question:
Number of people surveyed = 280
Percentage of people pleased = 65%
The number of people that were pleased will be:
= Percentage of people that were pleased × Number of people surveyed
= 65% × 280
= 65/100 × 280
= 0.65 × 280
= 182
182 people were pleased with the condition of the park
Anthony answered 76% of the questions on his math test correctly. There were 50 questions on the test. How many questions did Anthony answer correctly?
Answers
Hope this helped ;)
solve the system by Elimination x+8y=0 -4x-10y=22
Answers
Answer:
y = 1, x = -8
Step-by-step explanation:
[tex]x + 8y = 0\\-4x - 10y = 22[/tex]
we can multiply the top equation by 4 and cancel out the x's
[tex]4x + 32y = 0\\-4x - 10y = 22\\22y = 22\\y = 1[/tex]
[tex]x + 8(1) = 0\\x = -8\\-4(-8) - 10(1) \\32 - 10 = 22\\[/tex]
FIRST ONE CORRECT AND FIRST GETS BRAINLY.look at picture answer all questions.
Answers
Answer:
0,0
1,0.5
2, 1
3,1.5
4,2
Step-by-step explanation:
who ever gets my questions right will get 50 points
Answers
Answer:
what questions???
Step-by-step explanation:
Slope-intercept equation
Answers
Answer:
y=-3x+7
Step-by-step explanation:
(0,7) is the y-intercept and the b part of y=mx+b
m=-3 goes down by 3 whole units and 1 unit to the right. -3/1 = -3
Hope this helped ;)
The lengths of the sides of a quadrilateral are 4 consecutive even integers. The perimeter of the quadrilateral is 36 inches. What is the length of the longest side?\
WILL GIVE BRAINLIEST
NEED THIS ASAP
Answers
Answer:
The length of the longest side is 9 inches
Step-by-step explanation:
The given parameters for the quadrilateral is that the length of the sides are;
The length of the sides are consecutive integers = x, x + 2, x + 4, x + 6
The perimeter of the rectangle = 36 inches
The side length to be found = The length of the longest side = x + 3
2 6 10 14 18
∴ x + x + 2 + x + 4 + x + 6 = 36
4·x + 12 = 36
4·x = 36 - 12 = 24
4·x = 24
x = 24/4 = 6
x = 6 inches
The length of the longest side = x + 3 = 6 + 3 = 9
The length of the longest side = 9 inches.
Answer:
The length of the longest side is 9 inches
Step-by-step explanation:
The given parameters for the quadrilateral is that the length of the sides are;
The length of the sides are consecutive integers = x, x + 2, x + 4, x + 6
The perimeter of the rectangle = 36 inches
The side length to be found = The length of the longest side = x + 3
2 6 10 14 18
∴ x + x + 2 + x + 4 + x + 6 = 36
4·x + 12 = 36
4·x = 36 - 12 = 24
4·x = 24
x = 24/4 = 6
x = 6 inches
The length of the longest side = x + 3 = 6 + 3 = 9
The length of the longest side = 9 inches.
credit to oeerivona https://brainly.com/app/profile/18148767
Ron and Hermione are lifting feathers into the air with magic. Hermione can lift a feather 3{,}5253,5253, comma, 525 centimeters (\text{cm})(cm)left parenthesis, start text, c, m, end text, right parenthesis into the air. That is 555 times as high as Ron can lift a feather.
Answers
Answer:
705 cm
Step-by-step explanation:
Ron and Hermione are lifting feathers into the air with magic. Hermione can lift a feather 3,525
centimeters (cm) into the air. That is 5 times as high as Ron can lift a feather.
How high can Ron lift a feather with his magic?
Hermione = 3,525 cm
Hermione = 5 × Ron
Substitute Hermione = 3,525 cm into
Hermione = 5 × Ron
3,525 = 5 × Ron
Ron = 3,525 / 5
= 705
Ron = 705 cm
Answer: 705
Step-by-step explanation:
A person's running stride is about 1.14 times the person's height. Your friend's stride is 5.472 feet. How tall is your friend?
Answers
Round it I think ahah
Gary analyzes data on average outdoor temperature and the cost of air conditioning his home. He fits the data to a linear model and finds the correlation coefficient to be 0.96.
Select the words that accurately complete the statement:
Based on Gary's analysis, there is a _____ association between the increase in the outdoor temperature and the ______ in household air conditioning costs.
strong, increase
weak, decrease
strong, decrease
weak, increase
Answers
Answer:
the last one I had a blast in a row and a lot for
The first side of a triangle is 8 inches shorter than the second side. The third side is 4 times as long as the first side. The perimeter is 38 inches. What is the length of the longest side.
PLEASE HELP ME I NEED IT NOW
Answers
Answer:
20
Step-by-step explanation:
Let x be the first side.
Since x is 8 in. shorter than the second side, we know that we'd need to add 8 to x to get the length of the second side. So the second side is
x + 8 .
The third side is 4 times the length of the first side, so the third side is
4 x.
Perimeter is the sum of the sides, so:
( x)+(x+8)+4x=6x+8 (The 6x+8 is just combining like terms from the left side)
We also know the perimeter is 38, so we have:
6 x +8 = 38
subtract 8:
6 x=30
divide:
x =5.
The three sides have length: 5,13 , and 20.
The longest side is 20 inches long.
Lionel, Jill and Grace are all reading the same book. Lionel has read 31.5% of the book. Jill has read \binom{1}{3}( 3 1 ) of the book. Grace has read \binom{3}{8}( 8 3 ) of the book. Which list shows the numbers in order from greatest to least?
Answers
Answer:
Grace, Jill, Lionel
Step-by-step explanation:
Lionel, Jill and Grace are all reading the same book. Which list shows the numbers in order from greatest to least?
The first step is to convert to decimal numbers
For Lionel
Lionel has read 31.5% of the book.
= 31.5% = 31.5/100 = 0.315
For Jill
Jill has read 1/3 of the book.
= 1/3 = 0.33333333333
= 0.333
For Grace
Grace has read 3/8 of the book.
= 3/8 = 0.375
The, list shows the numbers in order from greatest to least
= Grace, Jill, Lionel
Where Grace is the greatest and Lionel is the least.
PLS ANSWER ASAP
which scatterplot suggest a linear relationship between x and y?
A) I only
B) III only
C) I and II only
D) I and III only
Answers
Answer:
B
Step-by-step explanation:
If you make a straight line it would go through the origin and have a constant rate
I need help please!!-
Answers
Answer:
tickets: $32
food: $18.14
drinks: $14.28
total: $64.42
3 * 4.75 = $14.25 for popcorn
$3.89 for candy
so you add $14.25 + 3.89 and you get the amount mike paid for food which is $18.14
2 * $4.39 = $8.78 for sodas
2 * $2.75 = $5.5 for waters
so you add $8.78 + $5.5 which is the amount paid for drinks which is $14.28
so he spent $69.42 for the family trip
Find the value of 'X' in the triangle below
Answers
Answer:
bottom right is 65 degrees, bottom left is 25 degrees, top is 90 degrees. x=12
Step-by-step explanation:
the angles if a triangle always add up to 180, lets make an equation
2x+1+5x+5+90=180
^^ we know that's 90 because there is a square for the angle, which means it's 90 degrees.
7x+96=180
7x=84
x=12
2(12)+1
25
5(12)+5
65
Kelsey has to pay $200 to rent a booth at the craft fair. The materials for each pendant cost $7.80, and she plans to sell each pendant for $13.50. To make a profit, she must make more money than she spends. Kelsey has already made 10 pendants.
Part C
It takes Kelsey 5 hours to make 12 pendants. If she works 8 hours per day for 3 days before the craft fair, can she make enough additional pendants to sell so that she can make a profit of at least $50? Explain.
Answers
Step-by-step explanation:
Let's calculate how much she will spend:
She has to pay $200 for the rent.
She made 10 pendants that costed $7.80 each, that's a total of 10*$7.80 = $78.
Therefore, she will spend $200 + $78 = $278.
Let's define x as the amount of pendants she makes.
To make a profit, the amount of pendants she makes, multiplied by $13.50 that is the price, has to be greater than $280 added to the amount of pendants she makes, multiplied by $7.80 that is the cost.
We write that as
13.50x > 280 + 7.80x
Let's subtract 7.80x on both sides:
13.50x -7.80x > 280 + 7.80x - 7.80x
5.70x > 280
Now we divide by 5.70 on both sides:
5.70x/5.70 > 280/5.70
x > 49.1
To make profit, she needs to make and sell more than 49 pendants.
If trapezoid ABCD is reflected over the x-axis and translated 5 units to the right, which is the resulting point of Point B?
Answers
Answer:
o
Step-by-step explanation:
A new health drink has 150% of the recommended daily allowance (RDA) for a certain vitamin. The RDA for this vitamin is 50 mg. How many milligrams of the vitamin are in the drink??
Answers
Answer:
75
Step-by-step explanation:
50*150% = 50*(1.5) = 75 (mg)
Answer:
75mg
Step-by-step explanation:
EASY - 3rd part
Need the following would you rather questions to be answered for a survey, need 5 people to answer
1) Would you rather be on house arrest or go to jail for a month?
2) Would you rather go to court and plead guilty or be placed on probation for 10 months?
3) Would you rather clean garbage alongside the road or speak to schools?
4) Would you rather go to solitary confinement for a year, or go to regular prison for 10?
5) Would you rather spend a half a lifetime in prison or a lifetime on probation?
Answers
1) I would rather be on house arrest for a month.
2) I would rather be placed on probation for 10 months.
3) I'd clean garbage around the road.
4) I'd rather go to solitary confinement for a year.
5) I'd rather spend half a lifetime on probation.
good luck on your survey!! have a great day :))
Answer:
1) I would rather be on house arrest for a month.
2) I would rather be placed on probation for 10 months.
3) I would rather speak to schools.
4) I would rather go to a solitary prison for a year.
5) I would rather spend half a lifetime in prison.
Step-by-step explanation:
f(x) = 2x+3 and g(x) = x - 7. Find f(3)
Answers
Answer:
f(3) = 9
Step-by-step explanation:
To evaluate f(3) substitute x = 3 into f(x), that is
f(3) = 2(3) + 3 = 6 + 3 = 9
Answer:
f(3) = 9
Step-by-step explanation:
f(3) = 2x + 3
input the 3 into all x values since it is f(x) basically it tells you the value of x
f(3) = 2(3) + 3
f(3) = 9
Can somebody help with grade6 math plzzz?
Answers
Answer:
Sure qhat is the question
-4(3x-6)-5x steps and solve
Answers
Answer:
Answer is 17x - 24
Step-by-step explanation:
First we have...
4(3x - 6) - 5x
We want to use distributive property first.
12x - 24 - 5x
Combine like terms...
12x - -5x - 24
And simplify.
17x - 24
This is as simplified as possible, you can't combine them anymore because one has an x, the other doesn't. I hope this helps, and I hope it's not wrong, but I do not think it is.
PLEASE HELP I WILL GIVE BRAINLEIST
Answers
Answer:
1. b 2. b 3. c 4. a 5. c
Step-by-step explanation:
hope this helps! i can give an explanation if needed
Answer:
What he said
Step-by-step explanation:
