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3 years ago

Solve for the value of n. (9n) (8n+8)

Mathematics

2 answers:

vekshin13 years ago

5 0

Answer:

you can't if there's no =

Step-by-step explanation:

12345 [234]3 years ago

5 0

Answer: undoable
Step by step explanation: no = so it’s no doable

You might be interested in

Power Series Differential equation

KatRina [158]

The next step is to solve the recurrence, but let's back up a bit. You should have found that the ODE in terms of the power series expansion for $y$

$\displaystyle\sum_{n\ge2}\bigg((n-3)(n-2)a_n+(n+3)(n+2)a_{n+3}\bigg)x^{n+1}+2a_2+(6a_0-6a_3)x+(6a_1-12a_4)x^2=0$

which indeed gives the recurrence you found,

$a_{n+3}=-\dfrac{n-3}{n+3}a_n$

but in order to get anywhere with this, you need at least three initial conditions. The constant term tells you that $a_2=0$ , and substituting this into the recurrence, you find that $a_2=a_5=a_8=\cdots=a_{3k-1}=0$ for all $k\ge1$ .

Next, the linear term tells you that $6a_0+6a_3=0$ , or $a_3=a_0$ .

Now, if $a_0$ is the first term in the sequence, then by the recurrence you have

$a_3=a_0$
$a_6=-\dfrac{3-3}{3+3}a_3=0$
$a_9=-\dfrac{6-3}{6+3}a_6=0$

and so on, such that $a_{3k}=0$ for all $k\ge2$ .

Finally, the quadratic term gives $6a_1-12a_4=0$ , or $a_4=\dfrac12a_1$ . Then by the recurrence,

$a_4=\dfrac12a_1$
$a_7=-\dfrac{4-3}{4+3}a_4=\dfrac{(-1)^1}2\dfrac17a_1$
$a_{10}=-\dfrac{7-3}{7+3}a_7=\dfrac{(-1)^2}2\dfrac4{10\times7}a_1$
$a_{13}=-\dfrac{10-3}{10+3}a_{10}=\dfrac{(-1)^3}2\dfrac{7\times4}{13\times10\times7}a_1$

and so on, such that

$a_{3k-2}=\dfrac{a_1}2\displaystyle\prod_{i=1}^{k-2}(-1)^{2i-1}\frac{3i-2}{3i+4}$

for all $k\ge2$ .

Now, the solution was proposed to be

$y=\displaystyle\sum_{n\ge0}a_nx^n$

so the general solution would be

$y=a_0+a_1x+a_2x^2+a_3x^3+a_4x^4+a_5x^5+a_6x^6+\cdots$
$y=a_0(1+x^3)+a_1\left(x+\dfrac12x^4-\dfrac1{14}x^7+\cdots\right)$
$y=a_0(1+x^3)+a_1\displaystyle\left(x+\sum_{n=2}^\infty\left(\prod_{i=1}^{n-2}(-1)^{2i-1}\frac{3i-2}{3i+4}\right)x^{3n-2}\right)$

4 0

3 years ago

I NEED HELP ASAP PLEASE!! ;)

Zigmanuir [339]

Answer:

7 inches

Step-by-step explanation:

First you have to find the average height of each class.

4th Grade:

56, 47, 54, 51, 53, 58, 48, 54, 46, 53

Then you have add it all up and divide it by how many students there are.

56 + 47 + 54 + 51 + 53 + 58 + 48 + 54 + 46 + 53 = 520

520 ➗10= 52

Same process for the 7th Grade.

You end up getting 52 and 59. You then Subtract it to get the answer to the question.

52 - 59= 7 inches

6 0

3 years ago

A family purchased tickets to a museum and spent a total of $45.00. The family purchased 5 tickets. There was $1.50 processing f

Arisa [49]

7.50$ for each ticket without the processing fee

4 0

3 years ago

1.) Use the following information to solve the questions. Kay sold 200

Yakvenalex [24]

9514 1404 393

Answer:

75 adult tickets
125 child tickets

Step-by-step explanation:

Let 'a' represent the number of adult tickets sold. Then (200-a) is the number of child tickets sold, and the revenue is ...

8a +5(200 -a) = 1225

3a = 225 . . . . . . . . . . subtract 1000, simplify

a = 75 . . . . . . . . . . . . .divide by 3

200 -a = 125

75 adult ($8) and 125 child ($5) tickets were sold.

<em>Additional comment</em>

The question asked here is "how many tickets did Kay sell?" The second line of your problem statement tells you the answer: "Kay sold 200 tickets ...". We have assumed that you are interested in the breakdown of tickets sold, even though that is not the question that is asked here.

3 0

4 years ago

To speed the process of surveying, surveyors use brass metal plates to record important information. The benchmarks, as they are

Agata [3.3K]

Answer:

Feet Above Sea Level

Step-by-step explanation:

A benchmark is a term in Surveying and Geo informatics, that describes a point of reference established at a known elevation which serves as basis in which other elevation or topographical point can be measured.

Therefore, when determining the benchmark, it's height is calculated relative to the vertical datum of the area, typically mean sea level, which is then recorded in FEET ABOVE SEA LEVEL.

Hence, Benchmarks measurements refer to FEET ABOVE SEA LEVEL.

5 0

3 years ago