Answer:
Step-by-step explanation:
area of top face = π15² = 225π in²
volume = 225π × 40 = 9000π ≅28,260 in³
In a certain animal species, the probability that a healthy adult female will have no offspring in a given year is 0.24, while the probabilities of 1, 2, 3, or 4 offspring are respectively 0.25, 0.19, 0.17, and 0.15. Find the expected number of offspring.
Answer:
The expected number of offspring is 2
Step-by-step explanation:
The given parameters can be represented as:
[tex]\begin{array}{cccccc}x & {0} & {1} & {2} & {3} & {4} \ \\ P(x) & {0.24} & {0.25} & {0.19} & {0.17} & {0.15} \ \end{array}[/tex]
Required
The expected number of offspring
This implies that we calculate the expected value of the function.
So, we have:
[tex]E(x) = \sum x * P(x)[/tex]
Substitute known values
[tex]E(x) = 0 * 0.24 + 1 * 0.25 + 2 * 0.19+ 3 * 0.17 + 4 * 0.15[/tex]
Using a calculator, we have:
[tex]E(x) = 1.74[/tex]
[tex]E(x) = 2[/tex] --- approximated
triangle ABC is similar to triangle XYZ. fine side a
Explanation:
The jump from 13 to 39 is "times 3" when comparing the diagonal segments. So the jump from 5 to 'a' must also be "times 3" to keep the sides in the same proportion. Therefore, a = 3*5 = 15.
Or we could solve it like so
13/39 = 5/a
13a = 39*5 ... cross multiplying
13a = 195
a = 195/13 .... dividing both sides by 13
a = 15
Which equation describe the line through the points (2,-4) and (5,8)
Answer:
Your equation would be
y=4x-12
Step-by-step explanation:
So an easy way to figure this out is graph the points and look at the distance the points are away from each other. In this case it was 12 up and 3 right. This is your slope. Simplify the fraction to 4/1. Then from (2,-4) use the given slope to work back to a point that is on the y axis, which is (0,12). Plug all of the given information you found into y=mx+b and you get the given formula.
Previous studies suggest that use of nicotine-replacement therapies and antidepressants can help people stop smoking. The New England Journal of Medicine published the results of a double-blind, placebo-controlled experiment to study the effect of nicotine patches and the antidepressant bupropion on quitting smoking. The target for quitting smoking was the 8th day of the experiment.
In this experiment researchers randomly assigned smokers to treatments. Of the 162 smokers taking a placebo, 28 stopped smoking by the 8th day. Of the 272 smokers taking only the antidepressant buproprion, 82 stopped smoking by the 8th day.
Calculate the 99% confidence interval to estimate the treatment effect of buproprion (placebo-treatment). (The standard error is about 0.0407. Use critical value z = 2.576.)
( ), ( )
Round your answer to three decimal places. Put lower bound in the first box and upper bound in the second box.
Using the z-distribution, it is found that the 99% confidence interval to estimate the treatment effect of buproprion (placebo-treatment) is (-0.234, -0.024).
What is a t-distribution confidence interval?The confidence interval is:
[tex]\overline{x} \pm zs[/tex]
In which:
[tex]\overline{x}[/tex] is the sample mean.z is the critical value.s is the standard error.In this problem, we are given that z = 2.576, s = 0.0407. The sample mean is the difference of the proportions, hence:
[tex]\overline{x} = \frac{28}{162} - \frac{82}{272} = -0.129[/tex]
Then, the bounds of the interval are given by:
[tex]\overline{x} - zs = -0.129 - 2.576(0.0407) = -0.234[/tex]
[tex]\overline{x} + zs = -0.129 + 2.576(0.0407) = -0.024[/tex]
The 99% confidence interval to estimate the treatment effect of buproprion (placebo-treatment) is (-0.234, -0.024).
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Twice a number is equal to five more than five times the number.
Write that into an equation
Answer:
2x=5y+5
Step-by-step explanation:
Let one number be x, other y
Twice a number(2x) is five more(+5) than 5 times the other number(5y),
It means 2x > 5y
By 5 more, so
2x=5y+5
All of the following are equivalent except
x-7
X-(-7)
-7+x
x+(-7)
Answer:
X-(-7)
Step-by-step explanation:
If you are subtract by a negative number it turns it into a positive. It would look like this: X+(+7)
A ball is thrown vertically upward from the ground. Its distance in feet from the ground in t seconds is s(t)=224t−16t. After how many seconds will the ball be 720 feet from the ground?
Answer:
s= 16t^2+128t, answer.......
A clock rotated from 12 to 6 this is
Answer:
one half
Step-by-step explanation:
Because the rotation from 12 to 6 is one-half of a complete rotation, it seems reasonable to assume that the hour hand is moving continuously and has therefore moved one-half of the distance between the 2 and the 3. source- ck12.org
A cylindrical tin has a radius of 3 cm. What is the shortes length of a string that can be wound once round the curved surface of the tin?(Takeby =3.14)
Answer:
[tex]\pi = \frac{22}{7} [/tex]
Use this OK bro.
The shortest length (circumference) of the string is 18.84cm.
What is the circumference?The circumference is that certain length that requires to enclose a circle with respective of a fixed length known as radius. If radius of cylinder be r, then the circumference will be 2πr.
How to calculate the shortest length of the string to wound the cylinder once?The required length of the string is the circumference of the base of the cylinder.
The radius of the cylinder is 3cm.
Taking π=3.14, the circumference will be : 2*3.14*3cm
=18.84cm
The shortest length of the string is 18.84cm.
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90:120 table to garbage can?
Answer:
wto
Step-by-step explanation:
tan inverse X + tan inverse Y + tan inverse z=pie prove that X+Y+Z=xyz
Answer:
see explanation
Step-by-step explanation:
Given
[tex]tan^{-1}[/tex]x + [tex]tan^{-1}[/tex]y + [tex]tan^{-1}[/tex] z = π
let
[tex]tan^{-1}[/tex]x = A , [tex]tan^{-1}[/tex]y = B , [tex]tan^{-1}[/tex]z = C , so
x = tanA, y = tanB , z = tanC
Substituting values
A + B + C = π ( subtract C from both sides )
A + B = π - C ( take tan of both sides )
tan(A + B) = tan(π - C) = - tanC ( expand left side using addition identity for tan )
[tex]\frac{tanA+tanB}{1-tanAtanB}[/tex] = - tanC ( multiply both sides by 1 - tanAtanB )
tanA + tanB = - tanC( 1 - tanAtanB) ← distribute
tanA+ tanB = - tanC + tanAtanBtanC ( add tanC to both sides )
tanA + tanB + tanC = tanAtanBtanC , that is
x + y + z = xyz
Solve each equation for the given variable
1.3(2x+4)=54
2.4+(5x+5)54
Please
Answer:
1. x = 7
2. 270x+274
Explanation:
see attached filed for step by step reasoning
0.003 is 1/10 of
Please help I need this for homework !!!!!!!!!!!!
Answer:
0.03
Step-by-step explanation:
32% adults favor the use of unmanned drones by police agencies. Twelve u.s. adults are randomly selected. Find the probability that the number of u.s. adults who favor the use of unmanned drones by police agencies is (a) exactly three, (b) at least four, (c) less than eight
Answer:
C
Step-by-step explanation:
32% of 12 =
32/100 x 12
= 3.84
So, C would be the correct choice
I wasn't sure about my answer so used the Gauthmath App
Here is data on the percentage of 200 hotels in each of the three large cities across the world on whether minibar charges are correctly posted at checkout are given below.
Hong Kong New York Paris
Yes 86% 76% 78%
No 14% 24% 22%
At the 0.05 level of significance, you want to know if there is evidence of a difference in the proportion of hotels that correctly post minibar charges among the three cities.
Referring to the table above the test will involve _________ degrees of freedom.
Referring to Scenario above, the expected cell frequency for the Hong Kong/Yes cell is _______?
Referring to Scenario above, the critical value of the test is ________. Use degrees of freedom and look at the chi-square distribution table.
Referring to Scenario above, the value of the test statistic is _________.
Answer:
Degree of freedom = 2
Expected frequency = 80%
Critical value, = 5.991
χ² statistic = 3.5
Step-by-step explanation:
Given the data :
Hong Kong New York Paris
Yes 86% 76% 78%
No 14% 24% 22%
The degree of freedom for the Chisquare statistic is given as :
(no of rows - 1) * (number of columns - 1)
Number of rows = 2
Number of columns = 3
. Degree of freedom = (2-1) * (3-1) = 1*2 = 2
Expected frequency = (Row total * column total) / grand total
The expected frequency of Hong Kong / Yes cell :
Row total = (86+76+78) = 240
Column total = (86+14) = 100
Grand total, N = (14+24+22)+240 = 300
Expected frequency = (240*100)/300 = 80%
The critical value :
At α - level = 0.05 ; df = 2
Critical value = 5.991
χ² = Σ(observed - Expected)² / Expected
The expected values :
80 80 80
20 20 20
Hence,
χ² = Σ(86-80)²/80 + (76-80)²/80 + (78-80)²/80 + (14-20)²/20 + (24-20)²/20 + (22-20)²/20
χ² statistic = 3.5
f(x)=|x| to the graph of g(x)=∣∣4+x∣∣?
Find the minimum sample size needed to be 99% confident that the sample's variance is within 30% of the population's variance.
The Minimum sample size table is attached below
Answer:
[tex]X=173[/tex]
Step-by-step explanation:
From the question we are told that:
Confidence Interval [tex]CI=99\%[/tex]
Variance [tex]\sigma^2=30\%[/tex]
Generally going through the table the
Minimum sample size is
[tex]X=173[/tex]
Michelle would like to know how much of her loan payments will go toward interest. She has a $124,500 loan with a 5.9% interest rate that is compounded monthly. The loan has a term of 10 years. Calculate the total amount of interest that Michelle will pay over the course of the loan.
9514 1404 393
Answer:
$40,615.20
Step-by-step explanation:
The amortization formula will tell you Michelle's monthly payment.
A = P(r/12)/(1 -(1 +r/12)^(-12t)) . . . . loan value P at interest rate r for t years
A = $124,500(0.059/12)/(1 -(1 +0.059/12)^(-12·10)) ≈ $1375.96
__
The total of Michelle's 120 monthly payments is ...
12 × $1375.96 = $165,115.20
This amount pays both principal and interest, so the amount of interest she pays is ...
$165,115.20 -124,500 = $40,615.20
Michelle will pay $40,615.20 in interest over the course of the loan.
__
A calculator or spreadsheet can figure this quickly.
Situation 1 Riverbed Cosmetics acquired 10% of the 215,000 shares of common stock of Martinez Fashion at a total cost of $12 per share on March 18, 2020. On June 30, Martinez declared and paid $74,000 cash dividend to all stockholders. On December 31, Martinez reported net income of $127,600 for the year. At December 31, the market price of Martinez Fashion was $13 per share.
Situation 2 Marin, Inc. obtained significant influence over Seles Corporation by buying 30% of Seles's 31,300 outstanding shares of common stock at a total cost of $9 per share on January 1, 2020. On June 15, Seles declared and paid cash dividends of $36,600 to all stockholders. On December 31, Seles reported a net income of $80,100 for the year.
Prepare all necessary journal entries in 2020 for both situations. (Credit account titles are automatically indented when amount is entered. Do not indent manually. If no entry is required, select "No Entry" for the account titles and enter for the amounts.)
Answer:
Riverbed Cosmetics and Martinez Fashion
March 18, 2020:
Debit Investment in Martinez Fashion $2,580,000
Credit Cash $2,580,000
To record the acquisition of 10% of the 215,000 shares of common stock
June 30, 2020:
Debit Cash $7,400
Credit Dividend Income $7,400
To record dividend income received ($74,000 * 10%).
December 31, 2020:
Debit Investment in Martinez Fashion $215,000
Credit Unrealized Gain $215,000
To record the unrealized gain from the increase in share price.
Situation 2:
Marin, Inc. and Seles Corporation
January 1, 2020:
Debit Investment in Seles Corporation $84,510
Credit Cash $84,510
To record the 30% of Seles's 31,300 shares acquired at a total cost of $9 per share.
June 15, 2020:
Debit Cash $10,980
Credit Investment in Seles Corporation $10,980
To record the 30% of $36,600 dividends paid to all stockholders.
December 31, 2020:
Debit Investment in Seles Corporation $24,030
Credit Retained Earnings $24,030
To record the company's share of the net income.
Step-by-step explanation:
a) Data and Analysis:
Riverbed Cosmetics and Martinez Fashion
March 18, 2020: Investment in Martinez Fashion $2,580,000 Cash $2,580,000 10% of the 215,000 shares of common stock
June 30, 2020: Cash $7,400 Dividend Income $7,400 ($74,000 * 10%)
December 31, 2020: Investment in Martinez Fashion $215,000 Unrealized Gain $215,000
Situation 2:
Marin, Inc. and Seles Corporation
January 1, 2020: Investment in Seles Corporation $84,510 Cash $84,510
30% of Seles's 31,300 outstanding shares of common stock at a total cost of $9 per share
June 15, 2020: Cash $10,980 Investment in Seles Corporation $10,980
30% of $36,600 paid to all stockholders.
December 31, 2020: Investment in Seles Corporation $24,030 Retained Earnings $24,030
Bill and Will, starting together, ran a 400-meter race, each running at a constant speed. When Bill crossed the finish line, Will was exactly 20 yards behind Bill. They decide to run the race again, this time Bill starting 20 yards behind the original starting line and each running at his same constant speed as before. This time _______ wins by _______ yards.
Answer: Bill, 1
Step-by-step explanation:
Given
Bill and will run a 400 yard race.
Bill win by 20 yard
Suppose the speed of Bill and Will are [tex]\mathbf{v_b}, \mathbf{v_w}[/tex]
time taken for them is same for the first time
[tex]\Rightarrow t_b=t_w\\\\\Rightarrow \dfrac{400}{v_b}=\dfrac{400-20}{v_w}\\\\\Rightarrow \dfrac{v_b}{v_w}=\dfrac{400}{380}\ or\ \dfrac{20}{19}\\[/tex]
Now Bill starts 20 yards behind the starting line
Ratio of their time to cover the distances is
[tex]\Rightarrow \dfrac{t_b}{t_w}=\dfrac{\dfrac{420}{v_b}}{\dfrac{400}{v_w}}\\\\\Rightarrow \dfrac{t_b}{t_w}=\dfrac{420}{400}\times \dfrac{v_w}{v_b}\\\\\Rightarrow \dfrac{t_b}{t_w}=\dfrac{21}{20}\times \dfrac{19}{20}\\\\\Rightarrow \dfrac{t_b}{t_w}=\dfrac{399}{400}[/tex]
The obtained ratio is less than 1. Thus, the time taken by Bill is less than Will.
For the same time Bill wins
[tex]\therefore \dfrac{v_b\times t}{v_w\times t}=\dfrac{420}{x}\\\\\Rightarrow x=19\times 21\\\Rightarrow x=399\ m[/tex]
Thus, Will has covered only 399 yards.
This time Bill wins by 1 yards.
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The sales tax for an item was $18.40 and it cost $460 before tax.
Find the sales tax rate. Write your answer as a percentage.
Answer:
4%
Step-by-step explanation:
item cost x sales tax rate = sales tax
460 x sales tax rate = 18.40
sales tax rate = 18.40/460
sales tax rate = .04 or 4%
The bell tower of the cathedral in Pisa, Italy, leans 5.6° from the vertical. A tourist stands 107 m from its base, with the tower leaning directly toward her. She measures the angle of elevation to the top of the tower to be 28.6°. Find the length of the tower to the nearest meter. m
Answer:
[tex]l=56m[/tex]
Step-by-step explanation:
From the question we are told that:
Angle from vertical [tex]\theta =5.6[/tex]
Horizontal Distance [tex]d=107m[/tex]
Angle of elevation [tex]\gamma=28.6[/tex]
Generally the Trigonometric equation for exterior angles is mathematically given by
[tex]Exterior\ angles=\sum of\ two\ interior\ angles[/tex]
Where
[tex]Exterior angles=90 \textdegree +5.6 \textdegree[/tex]
Therefore
[tex]90 \textdegree +\theta \textdegree=\omega+\gamma[/tex]
[tex]90 \textdegree +5.6 \textdegree=\omega+28.6 \textdegree[/tex]
[tex]\omega=67 \textdegree[/tex]
Generally the equation for The Sine rule is mathematically given by
[tex]\frac{sin \omega }{d}=\frac{sin \gamma}{l}[/tex]
[tex]l=\frac{107 sin 28.6}{sin 67 \textdegree }[/tex]
[tex]l=56m[/tex]
There are two rectangles Jared is examining. He knows the width of the first rectangle measures
2.48 cm, and the length is twice its width.
Jared also knows that the width of the second rectangle is equal to the length of the first rectangle,
and that the area of the second rectangle is 9.92. Given this information, find the length of the
second rectangle for Jared.
1st rectangle:
width: 2.48cm
length: 4.96
2nd rectangle:
width: 4.96 (equals to the length of the 1st rectangle)
area: 9.92
length: 9.92/4.96 = 2
Look at image to see question
Answer:
Does the answer help you
I'm not sure how to do this
Answer:
1 and 5 sevenths of a bag
Step-by-step explanation:
2/7 males half to it takes 4/7 to make a full one multiply 4 by 3 and you get 12/7 so that makes 1 and 5/7
Question 4 (2 marks)
Justin works 14 hours at a normal pay rate of $24.80 per hour and 5 hours of overtime at
time and a half. How much should he be paid?
I
809 words
LE
English (Australia)
Answer:
554.7
Step-by-step explanation:
The pay=25.8*14+(25.8)*5*1.5=554.7
mr. jones has a patio in the sahpe of a trapezoid. a round fountain having a circumference of 14 pi linear feet is placed in the corner as showin in the accompanying diagram. to the nearest square foot, how much of the patio s area ins not taken up by the fountanin? reall tha the circumferencie of a circle is calculated using c = 2
The area of the patio not taken up by the fountain is 241ft²
Please find attached an image of the patio
Area of the patio not taken up by the fountain = area of patio - area of fountain
The patio is in a shape of a trapezoid. Thus, the area of the patio can be determined by using the formula for the area of a trapezoid
A trapezoid is a convex quadrilateral. A trapezoid has at least on pair of parallel sides. the parallel sides are called bases while the non parallel sides are called legs
Characteristics of a trapezoid
It has 4 vertices It has 4 edges If both pairs of its opposite sides of a trapezoid are parallel, it becomes a parallelogramArea of a trapezoid = 0.5 x (sum of the lengths of the parallel sides) x height
Taking a look at the image, we are not provided with the height of the trapezoid, just the parallel sides and the hypotenuse.
Pythagoras theorem can be used to determine the the height of the trapezoid
The Pythagoras theorem : a² + b² = c²
where a = height
b = base = 20 ft - 12 ft = 8ft
8ft / 2 = 4
c = hypotenuse
a² + 4² = 25²
a² = 625 - 16
a² = 609
√609 = 24.68 ft
Area of the trapezoid = 0.5 x (20 + 12) x 24.68 = 394.88 ft²
The fountain is in the shape of a circle.
Area of a circle = πr²
Where : = π = pi = 22/7
R = radius
The radius would have to determined from the circumference
circumference of a circle = 2πr
14π = 2πr
r = 14π / 2π
r = 7
Area of the circle = [tex]\frac{22}{7}[/tex] × 7²
[tex]\frac{22}{7}[/tex] × 49 = 154 ft²
Area of the patio not taken up by the fountain = 394.88 ft² - 154 ft² = 240.88ft²
To round off to the nearest square, look at the first number after the decimal, if it is less than 5, add zero to the units term, If it is equal or greater than 5, add 1 to the units term.
The tenth digit is greater than 5, so one is added to 0. The number becomes 241ft²
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which data is represented by this plot?
a)2,4,0,4,6,3,1,7,8,1,1
b)0,1,2,3,4,5,6,7,8,0,1
c)0,2,3,0,2,4,4,5,7,8,7
d)1,2,6,4,7,7,2,2,0,1
A hospital director is told that 54% of the emergency room visitors are insured. The director wants to test the claim that the percentage of insured patients is under the expected percentage. A sample of 120 patients found that 60 were insured. Find the value of the test statistic. Round your answer to two decimal places.
Answer:
Z -0.879173965
Step-by-step explanation:
Z -0.879173965
ρ 0.5
π 0.54
n 120
The value of the test statistic is the z-score z = -0.88
What is a z-score?The relationship between a value and the mean of a set of values is expressed numerically by a Z-score. The Z-score is computed using the standard deviations from the mean. A Z-score of zero indicates that the data point's score and the mean score are identical.
The Z-score is calculated using the formula:
z = (x - μ)/σ
where z: standard score
x: observed value
μ: mean of the sample
σ: standard deviation of the sample
Given data ,
Let the test statistic value be represented as z
Now , the probability of emergency room visitors are insured is q = 0.54
The total number of patients n = 120
The number of patients that were insured = 60
So , the percentage of people that were insured p = 60/120 = 0.5
Now , test statistic value z = ( p - q ) / [ √ ( q ( 1 - q )/n² ]
The value of z score is
z = [ 0.5 - 0.54 ] / √ 0.54 ( 1 - 0.54 ) / 120²
On simplifying the equation , we get
The value of z score is z = -0.88
Hence , the test statistic is z = -0.88
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[infinity]
Substitute y(x)= Σ 2 anx^n and the Maclaurin series for 6 sin3x into y' - 2xy = 6 sin 3x and equate the coefficients of like powers of x on both sides of the equation to n= 0. Find the first four nonzero terms in a power series expansion about x = 0 of a general
n=0
solution to the differential equation.
У(Ñ)= ___________
Recall that
[tex]\sin(x)=\displaystyle\sum_{n=0}^\infty(-1)^n\frac{x^{2n+1}}{(2n+1)!}[/tex]
Differentiating the power series series for y(x) gives the series for y'(x) :
[tex]y(x)=\displaystyle\sum_{n=0}^\infty a_nx^n \implies y'(x)=\sum_{n=1}^\infty na_nx^{n-1}=\sum_{n=0}^\infty (n+1)a_{n+1}x^n[/tex]
Now, replace everything in the DE with the corresponding power series:
[tex]y'-2xy = 6\sin(3x) \implies[/tex]
[tex]\displaystyle\sum_{n=0}^\infty (n+1)a_{n+1}x^n - 2\sum_{n=0}^\infty a_nx^{n+1} = 6\sum_{n=0}^\infty(-1)^n\frac{(3x)^{2n+1}}{(2n+1)!}[/tex]
The series on the right side has no even-degree terms, so if we split up the even- and odd-indexed terms on the left side, the even-indexed [tex](n=2k)[/tex] series should vanish and only the odd-indexed [tex](n=2k+1)[/tex] terms would remain.
Split up both series on the left into even- and odd-indexed series:
[tex]y'(x) = \displaystyle \sum_{k=0}^\infty (2k+1)a_{2k+1}x^{2k} + \sum_{k=0}^\infty (2k+2)a_{2k+2}x^{2k+1}[/tex]
[tex]-2xy(x) = \displaystyle -2\left(\sum_{k=0}^\infty a_{2k}x^{2k+1} + \sum_{k=0}^\infty a_{2k+1}x^{2k+2}\right)[/tex]
Next, we want to condense the even and odd series:
• Even:
[tex]\displaystyle \sum_{k=0}^\infty (2k+1)a_{2k+1}x^{2k} - 2 \sum_{k=0}^\infty a_{2k+1}x^{2k+2}[/tex]
[tex]=\displaystyle \sum_{k=0}^\infty (2k+1)a_{2k+1}x^{2k} - 2 \sum_{k=0}^\infty a_{2k+1}x^{2(k+1)}[/tex]
[tex]=\displaystyle a_1 + \sum_{k=1}^\infty (2k+1)a_{2k+1}x^{2k} - 2 \sum_{k=0}^\infty a_{2k+1}x^{2(k+1)}[/tex]
[tex]=\displaystyle a_1 + \sum_{k=1}^\infty (2k+1)a_{2k+1}x^{2k} - 2 \sum_{k=1}^\infty a_{2(k-1)+1}x^{2k}[/tex]
[tex]=\displaystyle a_1 + \sum_{k=1}^\infty (2k+1)a_{2k+1}x^{2k} - 2 \sum_{k=1}^\infty a_{2k-1}x^{2k}[/tex]
[tex]=\displaystyle a_1 + \sum_{k=1}^\infty \bigg((2k+1)a_{2k+1} - 2a_{2k-1}\bigg)x^{2k}[/tex]
• Odd:
[tex]\displaystyle \sum_{k=0}^\infty 2(k+1)a_{2(k+1)}x^{2k+1} - 2\sum_{k=0}^\infty a_{2k}x^{2k+1}[/tex]
[tex]=\displaystyle \sum_{k=0}^\infty \bigg(2(k+1)a_{2(k+1)}-2a_{2k}\bigg)x^{2k+1}[/tex]
[tex]=\displaystyle \sum_{k=0}^\infty \bigg(2(k+1)a_{2k+2}-2a_{2k}\bigg)x^{2k+1}[/tex]
Notice that the right side of the DE is odd, so there is no 0-degree term, i.e. no constant term, so it follows that [tex]a_1=0[/tex].
The even series vanishes, so that
[tex](2k+1)a_{2k+1} - 2a_{2k-1} = 0[/tex]
for all integers k ≥ 1. But since [tex]a_1=0[/tex], we find
[tex]k=1 \implies 3a_3 - 2a_1 = 0 \implies a_3 = 0[/tex]
[tex]k=2 \implies 5a_5 - 2a_3 = 0 \implies a_5 = 0[/tex]
and so on, which means the odd-indexed coefficients all vanish, [tex]a_{2k+1}=0[/tex].
This leaves us with the odd series,
[tex]\displaystyle \sum_{k=0}^\infty \bigg(2(k+1)a_{2k+2}-2a_{2k}\bigg)x^{2k+1} = 6\sum_{k=0}^\infty (-1)^k \frac{x^{2k+1}}{(2k+1)!}[/tex]
[tex]\implies 2(k+1)a_{2k+2} - 2a_{2k} = \dfrac{6(-1)^k}{(2k+1)!}[/tex]
We have
[tex]k=0 \implies 2a_2 - 2a_0 = 6[/tex]
[tex]k=1 \implies 4a_4-2a_2 = -1[/tex]
[tex]k=2 \implies 6a_6-2a_4 = \dfrac1{20}[/tex]
[tex]k=3 \implies 8a_8-2a_6 = -\dfrac1{840}[/tex]
So long as you're given an initial condition [tex]y(0)\neq0[/tex] (which corresponds to [tex]a_0[/tex]), you will have a non-zero series solution. Let [tex]a=a_0[/tex] with [tex]a_0\neq0[/tex]. Then
[tex]2a_2-2a_0=6 \implies a_2 = a+3[/tex]
[tex]4a_4-2a_2=-1 \implies a_4 = \dfrac{2a+5}4[/tex]
[tex]6a_6-2a_4=\dfrac1{20} \implies a_6 = \dfrac{20a+51}{120}[/tex]
and so the first four terms of series solution to the DE would be
[tex]\boxed{a + (a+3)x^2 + \dfrac{2a+5}4x^4 + \dfrac{20a+51}{120}x^6}[/tex]