Substitute x = √7 sin(t) and dx = √7 cos(t) dt. Then
∫ √(7 - x²) dx = ∫ √(7 - (√7 sin(t))²) • √7 cos(t) dt
… = √7 ∫ √(7 - 7 sin²(t)) cos(t) dt
… = 7 ∫ √(1 - sin²(t)) cos(t) dt
… = 7 ∫ √(cos²(t)) cos(t) dt
We require that -π/2 ≤ t ≤ π/2 in order for the substitution we made to be reversible. Over this domain, cos(t) ≥ 0, so
√(cos²(t)) = |cos(t)| = cos(t)
and the integral reduces to
… = 7 ∫ cos²(t) dt
Recall the half-angle identity for cosine:
cos²(t) = (1 + cos(2t))/2
Then the integral is
… = 7/2 ∫ (1 + cos(2t)) dt
… = 7/2 (t + 1/2 sin(2t)) + C
… = 7t/2 + 7/4 sin(2t) + C
Get the antiderivative back in terms of x. Recall the double angle identity for sine:
sin(2t) = 2 sin(t) cos(t)
We have t = arcsin(x/√7), which gives
sin(t) = sin(arcsin(x/√7)) = x/√7
cos(t) = cos(arcsin(x/√7)) = √(7 - x²)/√7
Then
∫ √(7 - x²) dx = 7/2 arcsin(x/√7) + 7/4 • 2 sin(arcsin(x/√7)) cos(arcsin(x/√7)) + C
… = 7/2 arcsin(x/√7) + x/2 √(7 - x²) + C
Part C
What is the elevation of the deck where Winston ate dinner?
Answer: 10 feet
Step-by-step explanation:
(5z+17.6)-(-3z+12.2)
Unit 4 Solving Quadratic equations {and complex number}
Sammy's rabbit can eat 70 pounds of food in 80 days. Part A: At that same rate, how much food will Sammy need to feed his rabbit in 24 days? Part B: How long will it take his rabbit to eat 87.5 pounds of food? Part C: Suppose Sammy buys his rabbit a companion. Together, the rabbits need can eat 95 pounds of food in 65 days. Approximately how much food will Sammy need to buy in order to feed both rabbits inl year ( 365 daya)? Round to the nearest tenth.
Part A
The rabbit can eat 70 pounds of food in 80 days. The unit rate is 70/80 = 0.875 pounds of food per day. Multiply this with the 24 days to get the total amount eaten over that timespan.
24*0.875 = 21
Answer: 21 pounds of food=========================================================
Part B
x = number of days
The rabbit eats at a unit rate of 0.875 pounds per day. After x number of days pass by, the rabbit has eaten a total of 0.875x pounds of food. Set this equal to 87.5 and solve for x.
0.875x = 87.5
x = (87.5)/(0.875)
x = 100
Answer: 100 days=========================================================
Part C
This is is similar to part A, just with different numbers. We could follow those steps to get the answer, but I'll go another route.
Instead, I'll use a proportion to solve.
(95 pounds)/(65 days) = (x pounds)/(365 days)
95/65 = x/365
95*365 = 65*x
34675 = 65x
65x = 34675
x = 34675/65
x = 533.461538
x = 533.5
Answer: 533.5 pounds of fooda playground is 750 M long and 250 m broad find the cost of levelling at rupees 16 per 100 square metres
Answer:
Area of play ground = Length × Breadth = 750 × 250 = 187500. a Cost of levelling the ground = 187500 × 16 100 = Rs . 30000
What are the length and width of a rectangular traffic sign if the length exceeds the width by 4 inches and the perimeter is 152 inches?
Answer:
L = 40
w = 36
Step-by-step explanation:
P = 2*L + 2*w
L = w + 4
w = w
P = 152
P = 2*(w + 4) + 2*w Remove the brackets
P = 2w + 8 + 2w Combine and switch sides Use P = 152
4w + 8 = P
4w + 8 = 152 Subtract 8 from both sides.
4w = 152 - 8
4w = 144 Divide by 4
4w/w = 144/4
w = 36
L = w + 4
L = 36 + 4
L = 40
An automobile manufacturer produces 79% of its cars at plant A. If 5% of the cars manufactured at plant A have defective emissions control devices, what is the probability that one of this manufacturer's cars was manufactured at plant A and has a defective emissions control device?
Answer:
79
over
2000 or 79/2000 or 3.95%
Step-by-step explanation:
The probability that one of this manufacturer's cars was manufactured at plant A and has a defective emissions control device is 6.33%.
What is conditional probability?Conditional probability is a term used in probability theory to describe the likelihood that one event will follow another given the occurrence of another event.
Given, An automobile manufacturer produces 79% of its cars at plant A and 5% of the cars manufactured at plant A have defective emissions control devices.
∴ The probability that one of this manufacturer's cars was manufactured at plant A and has a defective emissions control device is,
= (5/79)×100%.
= 6.33%.
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#SPJ2
Solve the equation.
2
What is the first step to isolate the variable term on one side of the equation?
What is the second step to solve for x?
Please help and be fast
Answer:
Add 1/2x, Divide by 7/6
Step-by-step explanation:
Add 1/2x to both sides
Divide both sides by 7/6
Carl sold 32 sodas for $114 Medium sodas cost $300 and large sodas
cost $4.00 How many sodas of each size were sold?
Answer:
14 - medium sodas and 18 - large sodas
Step-by-step explanation:
x+y = 32 (the amount of medium and large sodas add up to 32)
3.00x + 4.00y = 114 (the cost of each soda = the amount of money made)
x = 32-y (isolate x and subsitiue it into the following equation)
3x+4y=114 --> 3(32-y) + 4y = 114
96 - 3y + 4y = 114
y=18
plug in 18 in to this equation x = 32-18, x=14
Name the triangle as described
Answer:
scalene triangle
Step-by-step explanation:
There are 9 3/5 pounds of bricks in the bag each brick weights 1 1/5 pounds ? How many bricks are in the bag
Answer:
there are 6 bricks in th ebag
Step-by-step explanation:
6 bricks in the bag.....
The path of a race will be drawn on a coordinate grid like the one shown below. The starting point of the race will be at (−5.3, 1). The finishing point will be at (1, −5.3).
Part A: For the -5.3, 1 it would be located in Quadrant Q because even though it just goes to -4 and 4 I can extend the grid in my head and that's how I was able to figure out.
Step-by-step explanation:
ayden evaluated the expression a ÷ (2 + 1.5) for a = 14. He said that the value of the expression was 8.5. Select all the statements that are true.
Jayden's solution is incorrect.
Jayden added inside the parentheses before dividing.
Jayden substituted the wrong value for a.
Jayden divided 14 by 2 and then added 1.5.
Jayden added inside the parentheses before multiplying.
Answer:
Jayden's solution is incorrect.
Jayden divided 14 by 2 and then added 1.5
Jayden substituted the wrong value for a.
John made 357$ for 17 hours of work.
At the same rate, how many hours would he have to work to make $237???
Answer: 14 hours
Step-by-step explanation: First I found the unit rate of how much money per hour. So, 357 divided by 17 = 21. So know I know that she earns 21$ per hour. Then, I did 237 divided by 17 which would be 13 remainder 16. Since he only get paid if he works for a full hour, I think the answer would be 14.
[tex]\begin{array}{ccll} \$&hrs\\ \cline{1-2} 357&17\\ 237&x \end{array}\implies \cfrac{357}{237}=\cfrac{17}{x}\implies \implies \cfrac{119}{79}=\cfrac{17}{x}\implies 119x=1343 \\\\\\ x = \cfrac{1343}{119}\implies x = \cfrac{79}{7}\implies x = 11\frac{2}{7}\leftarrow \textit{11 hours, 17 minutes and 8 seconds}[/tex]
Solve.
Sophia wants to buy a pair of shoes online. Shop X has a price of 35.90 CAD. The price at
Shop Y is 21 British pounds (GBP). Compare the prices using Canadian dollars. If 1 CAD =
0.75 GBP, which shop offers a better deal? Explain.
Answer:
Shop Y
Step-by-step explanation:
In order to compare, we need to make both the same units first. Since they give us the conversion factor 1 CAD=0.75 GBP, we can plug this in to the shoes from shop X. We get 35.90*0.75=26.93 GBP.
Now we can compare. Since 21 GBP < 26.93 GBP, we can see that shop Y's shoes are cheaper, and therefore the better deal.
A dugout needs to reach at least 54 feet below ground level. This means it needs to be more than 214 times its current depth. This depth is represented by the inequality 214d<−54, where d is the current depth of the dugout.
Select from the drop-down to correctly interpret the solution of this inequality.
The current depth of the dugout is
Choose...
feet below ground level.
Solving the inequality, it is found that:
The current depth of the dugout is of 0.25 feet below ground level.
The current depth of the dugout is of d.
The inequality below represents how much the dugout needs to reach, according to the current depth:
[tex]214d < -54[/tex]
We solve it similarly to an equality, hence:
[tex]d < -\frac{54}{214}[/tex]
[tex]d < -0.25[/tex]
The current depth of the dugout is of 0.25 feet below ground level.
A similar problem is given at https://brainly.com/question/14361489
Answer:
deeper then 24
Step-by-step explanation:
Please make me brainliest
jamie uses 54 buttons to make shirts. jamie uses 6 buttons to make each shirt. how many shirts did she make?
Answer: 9 shirts I think
Step-by-step explanation: 54/6=9
please help ill mark brainliest
= 60
( i dont know how to explain it , to many steps lol :3)
math problem need help give 5 stars and good rating if do
Answer:
The answer is A, 20%.
Step-by-step explanation:
If you find 30 out of 150, it is 20%. A simple way to do it is add 30 up until you get 150. So in this case it is 5 times. Then you do 100% divided by 5 which is 20%. Hope this helps!
Given the line segment AD. AD=24 BC=12,AB=CD Find AB ?
Answer:
I think its 6
Step-by-step explanation:
Sasha's SUV has a 17-gallon gas tank. The SUV gets an estimated 24 miles per gallon.
Approximately how many miles can the SUV run on half a tank of gas?
Answer:
The SUV can run 204 miles with half a gas of tank.
Step-by-step explanation:
Divide 17 by 2=8.5 gallons
Then do the formula for distance which is:
miles per gallon times gallon
24 times 8.5 would be 204
204 is your answer :3
152 feet in 16 seconds
Answer:
I'm not sure what you're asking but that is 9.5 feet per second.
Step-by-step explanation:
152÷16=9.5
Answer:
if you are asking about the unit rate it is 9.5 feet per second
Step-by-step explanation:
You just have to do 152/16
hope this helps
did I click the right one ?
Answer:
no its b
Step-by-step explanation:
Answer:
yup
Step-by-step explanation:
heeelllppp meeee please
Which of the following functions are solutions of the differential equation y" + y = 7 sin(x)? (Select all that apply.)
y = 7 sin(x)
y= 7 cos(x)
y= 7x sin(x) - 8x cos(x)
y = 7/2 sin(x)
Y = - 7/2 cos(x)
The homogeneous equation
y'' + y = 0
has characteristic equation
r² + 1 = 0
with roots at r = ± √(-1) = ± i, and so the characteristic solution is
y = C₁ cos(x) + C₂ sin(x)
Using the method of undetermined coefficients, suppose
y = a x cos(x) + b x sin(x)
(we would normally consider y = a cos(x) + b sin(x), but cos(x) and sin(x) are already part of the characteristic solution)
The derivatives are
y' = a cos(x) - a x sin(x) + b sin(x) + b x cos(x)
y' = (b - a x) sin(x) + (a + b x) cos(x)
and
y'' = -a sin(x) + (b - a x) cos(x) + b cos(x) - (a + b x) sin(x)
y'' = (-2a - b x) sin(x) + (2b - a x) cos(x)
Then
y'' + y = (-2a - b x) sin(x) + (2b - a x) cos(x) + a x cos(x) + b x sin(x)
7 sin(x) = -2a sin(x) + 2b cos(x)
and it follows that a = -7/2 and b = 0.
So, the general solution to the DE is
y = C₁ cos(x) + C₂ sin(x) - 7/2 x cos(x)
which means the only valid solutions from the given choices are
y = 7 sin(x)
y = 7 cos(x)
graph the line indicated by the slope, m = - 3, and passing through the point (-4, 1) .
The equation of a line in point slope form is expressed according to the formula;
y-y0 = m(x-x0)
m is the slope of the line(x0, y0) is any point on the lineGiven the following parameters
m = -3
(x0, y0) = (-4, 1)
Substitute into the formula above will givee;
y - 1 = -4(x+4)
y -1 = -4x - 16
y = -4x - 15
Next is to plot the graph of the line y = -4x - 15 on the coordinate plane as shown:
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Jabari drives 20.4 miles in 17 minutes. He passes a sign which gives the speed limit as 55 mph. By how much, in mph, did Jabari's average speed exceed the speed limit?
Jabari's average speed exceed the speed limit by 17 miles per hour
Given:
Total distance = 20.4 miles
Time taken = 17 minutes
convert minutes to hour
60 minutes = 1 hour
17 minutes = 0.283333 hour
Average speed = Total distance ÷ Time taken
= 20.4 ÷ 0.283333
= 72.00008470598200
Approximately, 72 miles per hour
Speed limit = 55 miles per hour
Exceeded speed limit = 72 - 55
= 17 miles per hour
Therefore, Jabari's average speed exceed the speed limit by 17 miles per hour
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What is auto insurance?
Answer:
the second option.
a policy that pays to get your vehicle replaced or repaired incase of an accident.
Step-by-step explanation:
Here is the list of numbers.
5
11
16
24
29
From the list, write down a multiple of 3.
Plz write down the answer.
Answer:
From the list the multiple of 3 is 24
Much help needed thanks!