Proceed as in Example 4 in Section 6.1 and find a power series solution y = [infinity] n = 0 cnxn of the given linear first-order differential equation. (Give your answer in terms of c0.) y' = xy

Answers

Answer 1

Let y be a solution to the given differential equation,

[tex]y' = xy[/tex]

where

[tex]\displaystyle y = \sum_{n=0}^\infty c_n x^n \\\\ y' = \sum_{n=0}^\infty nc_nx^{n-1} = \sum_{n=1}^\infty nc_nx^{n-1} = \sum_{n=0}^\infty (n+1)c_{n+1}x^n[/tex]

Substituting these series into the DE gives

[tex]\displaystyle \sum_{n=0}^\infty (n+1)c_{n+1}x^n = x\sum_{n=0}^\infty c_nx^n \\\\ \sum_{n=0}^\infty (n+1)c_{n+1}x^n = \sum_{n=0}^\infty c_nx^{n+1} \\\\ \sum_{n=0}^\infty (n+1)c_{n+1}x^n = \sum_{n=1}^\infty c_{n-1}x^n \\\\ c_1 + \sum_{n=1}^\infty (n+1)c_{n+1}x^n = \sum_{n=1}^\infty c_{n-1}x^n \\\\ c_1 + \sum_{n=1}^\infty \bigg((n+1)c_{n+1}-c_{n-1}\bigg)x^n = 0[/tex]

Then the coefficients [tex]c_n[/tex] in the series solution are governed by the recurrence,

[tex]\begin{cases}c_0 = c_0 \\ c_1 = 0 \\ (n+1)c_{n+1}-c_{n-1} = 0&\text{for }n\ge1\end{cases}[/tex]

We have

[tex](n+1)c_{n+1}-c_{n-1} = 0 \implies nc_n - c_{n-2} = 0 \implies c_n = \dfrac{c_{n-2}}n[/tex]

so it follows that [tex]c_1=c_3=c_5=\cdots = 0[/tex], while

[tex]c_0 = \dfrac{c_0}1 = \dfrac{c_0}{2^0\times0!} \\\\ c_2 = \dfrac{c_0}2 = \dfrac{c_0}{2^1\times1!}\\\\ c_4 = \dfrac{c_2}4 = \dfrac{c_0}{2\times4} = \dfrac{c_0}{2^2\times2!}\\\\ c_6 = \dfrac{c_4}6 = \dfrac{c_0}{2\times4\times6} = \dfrac{c_0}{2^3\times3!}[/tex]

and so on, with the general n-th coefficient being

[tex]c_n = \begin{cases}0&\text{if }n\text{ is odd} \\ \dfrac{c_0}{2^{n/2}\left(\frac n2\right)!} &\text{if }n\text{ is even}\end{cases}[/tex]

Then the power series solution is

[tex]\displaystyle y(x) = c_0 \sum_{n=0}^\infty \frac{x^n}{2^{n/2}\left(\frac n2\right)!} = c_0 \sum_{n=0}^\infty \frac1{\left(\frac n2\right)!} \left(\frac x{\sqrt2}\right)^n[/tex]

but this doesn't tell the whole story because it doesn't capture the odd-index-is-zero case.

More concisely: let n = 2k for integers k ≥ 0. Then

[tex]\displaystyle y(x) = c_0 \sum_{k=0}^\infty \frac{x^{2k}}{2^k k!} = c_0 \sum_{k=0}^\infty \frac1{k!} \left(\frac{x^2}2\right)^k[/tex]

and as a bonus, it's easier to get an exact solution for this DE,

[tex]y(x) = c_0e^{x^2/2}[/tex]


Related Questions

A maker of microwave ovens advertises that no more than 10% of its microwaves need repair during the first 5 years of use. In a random sample of 50 microwaves that are 5 years old, 12% needed repairs at a=.04 can you reject the makers claim that no more than 10% of its microwaves need repair during the first five years of use?

Answers

Answer:

We conclude that no more than 10% of its microwaves need repair during the first five years of use.

Step-by-step explanation:

We are given that a maker of microwave ovens advertises that no more than 10% of its microwaves need repair during the first 5 years of use.

In a random sample of 50 microwaves that are 5 years old, 12% needed repairs.

Let p = population proportion of microwaves who need repair during the first five years of use.

So, Null Hypothesis, [tex]H_0[/tex] : p [tex]\leq[/tex] 10%      {means that no more than 10% of its microwaves need repair during the first five years of use}

Alternate Hypothesis, [tex]H_A[/tex] : p > 10%     {means that more than 10% of its microwaves need repair during the first five years of use}

The test statistics that will be used here is One-sample z-test for proportions;

                        T.S.  =  [tex]\frac{\hat p-p}{\sqrt{\frac{p(1-p)}{n} } }[/tex]  ~ N(0,1)

where, [tex]\hat p[/tex] = sample proportion of microwaves who need repair during the first 5 years of use = 12%

           n = sample of microwaves = 50

So, the test statistics =  [tex]\frac{0.12-0.10}{\sqrt{\frac{0.10(1-0.10)}{50} } }[/tex]

                                    =  0.471

The value of z-test statistics is 0.471.

Now, at a 0.04 level of significance, the z table gives a critical value of 1.751 for the right-tailed test.

Since the value of our test statistics is less than the critical value of z as 0.471 < 1.751, so we have insufficient evidence to reject our null hypothesis as the test statistics will not fall in the rejection region.

Therefore, we conclude that no more than 10% of its microwaves need repair during the first five years of use.

factorize : ( p- q ) cube​

Answers

Answer:

[tex]( {p - q}^{3} ) \\ = {p}^{2} - 3 {p}^{2} q + 3p {q}^{2} - {q}^{3} [/tex]

Hope my answer helped u :)

What do these have in common

Answers

Answer:

All Equal to 0

Step-by-step explanation:

0 = 0

3 - 3 = 0

0/4 = 0

12 - 3*4 = 0

Eleanor scores 680 on the mathematics part of the SAT. The distribution of SAT math scores in recent years has been Normal with mean 527 and standard deviation 118.
Gerald takes the ACT Assessment mathematics test and scores 27. ACT math scores are Normally distributed with mean 20 and standard deviation 3.
1. What is Elanor's standardized score?
Round to 2 decimal places.
3. What is Gerald's standardized score?
Round to 2 decimal places.
4. Assuming that both tests measure the same kind of ability, who has the higher score?
i. Gerald.
ii. Elanor.
iii. They both did equally well.

Answers

Answer:

1. Elanor's standardized score is  1.19

2. Gerald's standardized score is 0.72

3. Elanor has higher score.

Step-by-step explanation:

To compare Elanor's and Gerald's math scores, we need to standardize them and calculate their z-scores.

z score can be calculated using the formula

z=X-M over 8 where

X is the student's score

M is the mean score of the exam

s is the standard deviation of the exam

Elanor's standardized score is:

z(e) =680-554 over 106 ≈ 1.19

         

Gerald's standardized score is:

z(g)= 27 - 24.7 over 3.2 ≈ 0.72

Since z(e) > z(g), Elanor has higher score

Find the total surface area of the farm silo in a farmer's field. Use π = 3.14. pls help asap uwu

Answers

Answer:

A) 1236 units²

Step-by-step explanation:

Cylinder = 2[tex]\pi[/tex]h+2[tex]\pi[/tex]r²

2(3.14)(7.5)(15)+2(3.14)(7.5x7.5)

706.5+353.25=1059.75

1/2 Sphere = 1/2(4)[tex]\pi[/tex]r²

2(3.14)(7.5)(7.5)

353.25

TOTAL: 1059.75+353.25=1413

HOWEVER...you need to subtract the top of the cylinder ([tex]\pi[/tex]r²) 176.625

1413-176.625=1236.375

So the answer would be A.  (Silo’s do have a bottom, or else the answer would be D)

Answer:

1,236 units²

Step-by-step explanation:

I got it correct on founders edtell and screenshot below as proof

tentukan himpinan penyelasaian dari plsv berikut. A:3x+=2x+12​

Answers

Answer:

x=12

Step-by-step explanation:

3x=2x+12

3x-2x=12

x=12

The time between consecutive uses of a vending machine is exponential with an average of 15 minutes. a)Given that the machine has not been used in the previous 5 minutes, what is the probability that the machine will not be used during the next 10 minutes

Answers

Answer5

Step-by-step explanation:

Please help with this, thanks

Answers

Answer:

BDC is half of mBC = 11°

Easily you see that C is A + BDC = 23°

Since C = 23° so mDC is twice = 46°

x

If √2x - 1 + 2=5, then x is equal to?

Answers

Answer:

x = 5

Step-by-step explanation:

Remove the radical by raising each side to the index of the radical.

x = 5

This was done assuming that 2x-1 was under the radical and that +2 wasn't.

3(8a - 5b) – 2(a + b); use a = 3 and b = 2

Answers

Answer:

32

Step-by-step explanation:

3(8(3)-5(2))-2((3)+(2))

3(24-10) -2(5)

3(14) -10

42-10

32

[tex]\huge\text{Hey there!}[/tex]

[tex]\huge\textsf{3(8a - 5b) - 2(a + b)}\\\\\huge\textsf{= 3(8(3) - 5(2)) - 2(3 + 2)}\\\\\huge\textsf{= 3(24 - 10) - 2(3 + 2)}\\\\\huge\textsf{= (3)(14) - 2(3 + 2)}\\\\\huge\textsf{= 42 - 2(3 + 2)}\\\\\huge\textsf{= 42 - 2(5)}\\\\\huge\textsf{= 42 - 10}\\\\\huge\textsf{= 32}}[/tex]

[tex]\huge\boxed{\textsf{Answer: 32}}\huge\checkmark[/tex]

[tex]\huge\text{Good luck on your assignment \& enjoy your day!}[/tex]

~[tex]\huge\boxed{\frak{Amphitrite1040:)}}[/tex]

how many solutions are there to this non-linear systems/graph a. one solution,b.two solutions,c.no solutions

Answers

Photo of the graph?

This is the ASVAB question If 500 people are at a concert and 70% are adults. How many children are there?

Answers

Answer:

150

Step-by-step explanation:

70% of 500 people are adults and the remainder are children.

30% of 500 are children30*500/100= 150

There are 150 children

1. Why is money better than a bartering system?
A People might not have items to trade.
B It helps people to agree on the value of something.
C People might lose track of their money.
D Both A and B
E Both B and C

Answers

The correct answer is D. Both A and B

Explanation:

Bartering is an economic system in which products are directly exchanged for other products. For example, a pound of oranges is exchanged for a pound of rice. Due to this, in bartering, there is no money or elements such as coins or bills that represent the value of products or services. This system has both advantages and disadvantages in comparison to the use of money.

In terms of disadvantages, bartering implies individuals need products or services they can use to exchange, which might not be possible for all individuals as not all individuals might produce a product or have a product other are interested in. Also, in bartering the value of products varies, for example, a pound of blueberries can be equal to a pound of rice, three pounds of rice, or even half pound of rice, as values change according to the situation of those participating in the exchange. This means, in bartering the value fluctuates and it is more difficult to agree on the value of something, which does not occur if money is used as each product has a defined price which might just vary slightly. According to this, options A and B are advantages of money over bartering.

How far apart are the 2 cities? See picture.
Show steps

Answers

9514 1404 393

Answer:

  373 miles

Step-by-step explanation:

The difference in latitude is ...

  39.1° -33.7° = 5.4° = 0.54°(π/180°) radians = 0.03π radians

The arc length is given by ...

  s = rθ, where θ is the angle in radians

The length of the arc along the longitude line is ...

  s = (3960 mi)(0.03π) ≈ 373 mi

The distance from Atlanta to Cincinnati is about 373 miles.

This graph shows the US unemployment rate from August 2010 to November 2011.
Sample Unemployment Rate
Graph
Unemployment Rate
10%
80%
6%
Unemployment Rate
Aug 10
Jan 11
Jun 11
Nov 11
This graph suggests unemployment in the United States
O will continue to fall.
O will continue to rise.
O will remain the same.
O will only change a little.

Answers

Answer: Will continue to rise

Step-by-step explanation:

Looking at the graph one notices that after a slight dip in the unemployment rate from August 2010 to January 2011, the unemployment rate began to rise and by November 2011 was still rising.

The arrow on the graph serves to indicate the direction the unemployment rate is going and as it is pointing upwards, this means that the Unemployment rate will continue to rise.

This was down to the fact that in 2011 the US was still yet to recover from the Great Recession of 2008 - 2009.

Answer:

EDGE 2021

Step-by-step explanation:

1) 4%

2) Increase

The data recorded in following Table 1 shows the length of Medical checkup conducted by a Health & safety team, in meters,

20 25 33 47 39 41 21
39 33 32 38 41 37 49
59 60 31 28 48 36 60
b) Find the Mean and Median of the minutes.
c) Find Standard deviation also comment on the result.
d) Sketch Histogram and Frequency Polygon.

Answers

Answer:

yggnvfghg46777tuutyuyt6yffttgdfhurdvhu

The waves of a tsunami are 25 ft high, 90 miles apart, and traveling at a rate of 540 miles per hour. How long does it take for the waves to complete one period

Answers

Answer:

it will take 450 wave to complete

what is the tan invers of 3i/-1-i​

Answers

z = 3i / (-1 - i )

z = 3i / (-1 - i ) × (-1 + i ) / (-1 + i )

z = (3i × (-1 + i )) / ((-1)² - i ²)

z = (-3i + 3i ²) / ((-1)² - i ²)

z = (-3 - 3i ) / (1 - (-1))

z = (-3 - 3i ) / 2

Note that this number lies in the third quadrant of the complex plane, where both Re(z) and Im(z) are negative. But arctan only returns angles between -π/2 and π/2. So we have

arg(z) = arctan((-3/2)/(-3/2)) - π

arg(z) = arctan(1) - π

arg(z) = π/4 - π

arg(z) = -3π/4

where I'm taking arg(z) to have a range of -π < arg(z) ≤ π.

PLZ HELP ME I NEED HELP PLZZZ
There are 6 red marbles, 9 blue marbles, and 10 green marbles in a bag.

What is the theoretical probability of randomly drawing either a blue marble or a green marble?

36%
76%
19%
40%

Answers

Answer:

76%

Step-by-step explanation:

Total Outcomes (9 blue + 10 green)/Total options (9+10+6)

19/25

=76%

In a two-factor analysis of variance, the F-ratios for factor A, factor B, and the AxB interaction _____. Group of answer choices may have different df values but they all have the same denominator all have the same df values and they all have the same denominator may have different df values and may have different denominators all have the same df values but they may have different denominators

Answers

Answer:

may have different df values but they all have the same denominator

Step-by-step explanation:

In a two-factor analysis of variance, the F-ratios for factor A, factor B, and the AxB interaction _____. may have different df values but they all have the same denominator

In two--factor analysis of variance, the estimates of the variance can be obtained by partitioning the total sum of squares into three components corresponding to the three possible sources of variation , viz; Between Rows, Between Columns, and Within Samples or error.

As the number of rows and columns may differ the degrees of freedom differ with them.

In other words

Total df= Rows df + Columns df + Error df

Since the variance is identically the same for each row of the c values and variance is the same for each observation in the jth column of r values the sum of squares becomes an identity.

Therefore it may have different df values but they all have the same denominator.

Use the probability distribution table to answer the question.
What is P(1 < X < 5)?
Enter your answer, as a decimal, in the box.

Answers

Answer: 0.51

Add up the P(x) values that correspond to x = 2 through x = 4

0.07+0.22+0.22

So we have a 51% chance of getting an x value such that 1 < x < 5

By using the probability distribution table, the value of P(1<x<5) is 0.51

What is Probability?

Probability is the branch of mathematics concerning numerical descriptions of how likely an event is to occur, or how likely it is that a proposition is true

What is Probability distribution?

A probability distribution is the mathematical function that gives the probabilities of occurrence of different possible outcomes for an experiment. It is a mathematical description of a random phenomenon in terms of its sample space and the probabilities of events

Given,

We have to find the value of P(1<x<5)

P(1<x<5) = P(2)+P(3)+P(4)

P(2)=0.07

P(3)=0.22

P(4)=0.22

P(1<x<5) = 0.07+0.22+0.22 =0.51

Hence, the value of P(1<x<4)= 0.51

Learn more about Probability and Probability distribution here

https://brainly.com/question/14210034

#SPJ2

Time

(minutes)

Water

(gallons)

1

16.50

1.5

24.75

2

33

find the constant of proportionality for the second and third row

Answers

Answer:

16.50

Step-by-step explanation:

Constant of proportionality = no of gallons of water per 1 minute.

In the first row, we have 16.50 gallons of water per 1 minute.

In the 2nd row, we have 24.75 gallons of water in 1.5 minutes. In 1 minute, we will have 24.75 ÷ 1.5 = 16.50 gallons

In the 3rd row, we have 33 gallons in 2 minutes. In 1 minute, we will have 33 ÷ 2 = 16.50 gallons.

We can see that there seems to be the same constant of proportionality for the 2nd and 3rd row, which is 16.50.

Thus, a relationship between gallons of water (w) and time (t), considering the constant, 16.50, can be written as: [tex] w = 16.50t [/tex]

This means the constant of proportionality, 16.50, is same for all rows.

Please help 1-7 questions

Answers

Answer:

25= q+20

25 - 20 =q

5 = q

Hi there! Hopefully this helps!

-------------------------------------------------------------------------------------------

Answer: q = 5.~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

[tex]25 = q + 20[/tex]

Swap sides so that all variable terms are on the left hand side.

[tex]q + 20 = 25[/tex]

Subtract 20 from both sides.

[tex]q = 25 - 20[/tex]

Subtract 20 from 25 to get, you guessed it, 5!

Evaluate (657.3÷10)-(94.5÷5)

Answers

Answer:

Ans; (657.3÷10)-(94.5÷5) = 65.73 – 18.9 = 46.83

I hope I helped you^_^

Drag the tiles to the correct boxes to complete the pairs.
Match each given domain of the function f(I):
with its corresponding range.
{40, 45, 50, 55, 60)
{52, 56, 63, 67, 71}
{37, 46, 49, 55, 57)
{44, 51, 59, 66, 73}
Range
Domain
{20.8, 22.4. 25.2, 26.8, 28.4) <
{16, 18, 20, 22, 24)
(17.6, 20.4, 23.6, 26.4, 29.2)
(14.8, 18.4, 19.6, 22, 22.8)

Answers

(40, 45, 50, 55, 60) to (16, 18, 20, 22, 24)

{52, 56, 63, 67, 71} to {20.8, 22.4. 25.2, 26.8, 28.4}

{37, 46, 49, 55, 57} to (17.6, 20.4, 23.6, 26.4, 29.2)

{44, 51, 59, 66, 73} to (14.8, 18.4, 19.6, 22, 22.8)

Domain is the set of all values for which the function is defined. Range is the set of value inside the domain function.

The ranges and domain functions are given which needs to be matched correctly.

This also referred to as input and output function which will create a range and domain function.

Learn more at https://brainly.com/question/24378415

Answer:

I did the test and got this so just change these two and it will be correct

Step-by-step explanation:

I did test on edmentum/PLATO

4/2÷4/7? plz help me ​

Answers

Answer:

2

Step-by-step explanation:

4/2÷4/7

= 4/2 × 7/4

= 28/14

= 2

Do you think we would have had a civil war to end slavery if we had not expanded west and taken territory from Mexico? Thinking about Manifest Destiny, the Texas Revolution, and The Mexican American War, do you think the choice to expand sparked a civil war or do you think westward expansion had nothing to do with the civil war?

Answers

I think we would have still had the civil war, the civil war was many about freeing the enslaved persons, and the war was mainly between the North and South

the terms in this sequence increase by the same amount each time. _19_ _ 34_ a) work out the missing terms.

Answers

Answer:

The sequence is 14, 19, 24, 29, 34, 39.

Step-by-step explanation:

Let's call the common difference (the difference between two consecutive terms) as d. We see that the second term is 19 and the 5th term is 34 and since 5 - 2 = 3, we add d 3 times to 19 to get 34 so therefore:

19 + 3d = 34

3d = 15

d = 5 so the first term is 19 - 5 = 14, the third would be 19 + 5 = 24, the fourth would be 24 + 5 = 29 and the sixth would be 34 + 5 = 39.

5. When looking at a map, a student realizes that Birmingham is nearly due west of Atlanta, and Nashville is nearly due north of Birmingham. If the distance from Atlanta to Birmingham is roughly 150 mi, and the distance from Birmingham to Nashville is roughly 200 mi, what is the estimated distance from Atlanta to Nashville?

Answers

Answer: 250 mi

Step-by-step explanation:

Here we can think in a triangle rectangle:

The distance from Birmingham to Atlanta is roughly 150 mi, and this is one of the cathetus.

And the distance from Birmingham to Nashville is roughly 200 mi, this is the other cathetus of the triangle.

Now, the distance from Atlanta to Nashville will be the hypotenuse of this triangle rectangle.

Now we can apply the Pythagorean's theorem:

A^2 + B^2 = H^2

Where A and B are the cathetus, and H is the hypotenuse:

Then:

H = √(A^2 + B^2)

H = √(150^2 + 200^2) mi = √(62,500) mi = 250 mi

Then the estimated distance from Atlanta to Nashville is 250 mi

Approximately how many times greater is
7.4 x 10^8
than
2.5 x 10^7
0.3
3
30
300

Answers

Answer:

30

Step-by-step explanation:

To compare the numbers, divide the first number by the second number.

(7.4 x 10^8)/(2.5 x 10^7) = (74 x 10^7)/(2.5 x 10^7) = 74/2.5 = 29.6

Answer: 30

7.4 x 10^8= 740000000
2.5 x 10^7: 25000000

Answers If You Use The Other Numbers
x0.3= 7500000
x3= 75000000
x30= 750000000
x300= 7500000000

Answer: Not Possible

If You Did 7.5 x 10^8 it will make more sense but you didn’t so the answer is unspecified.
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