What is the missing fraction on the spinner? some1 helppp

Olin [163]

With $2L=\pi$ , the Fourier series expansion of $f(x)$ is

$\displaystyle f(x)\sim\frac{a_0}2+\sum_{n\ge1}a_n\cos\dfrac{n\pi x}L+\sum_{n\ge1}b_n\sin\dfrac{n\pi x}L$
$\displaystyle f(x)\sim\frac{a_0}2+\sum_{n\ge1}a_n\cos2nx+\sum_{n\ge1}b_n\sin2nx$

where the coefficients are obtained by computing

$\displaystyle a_0=\frac1L\int_0^{2L}f(x)\,\mathrm dx$
$\displaystyle a_0=\frac2\pi\int_0^\pi f(x)\,\mathrm dx$

$\displaystyle a_n=\frac1L\int_0^{2L}f(x)\cos\dfrac{n\pi x}L\,\mathrm dx$
$\displaystyle a_n=\frac2\pi\int_0^\pi f(x)\cos2nx\,\mathrm dx$

$\displaystyle b_n=\frac1L\int_0^{2L}f(x)\sin\dfrac{n\pi x}L\,\mathrm dx$
$\displaystyle b_n=\frac2\pi\int_0^\pi f(x)\sin2nx\,\mathrm dx$

You should end up with

$a_0=0$
$a_n=0$
(both due to the fact that $f(x)$ is odd)
$b_n=\dfrac1{3n}\left(2-\cos\dfrac{2n\pi}3-\cos\dfrac{4n\pi}3\right)$

Now the problem is that this expansion does not match the given one. As a matter of fact, since $f(x)$ is odd, there is no cosine series. So I'm starting to think this question is missing some initial details.

One possibility is that you're actually supposed to use the even extension of $f(x)$ , which is to say we're actually considering the function

$\varphi(x)=\begin{cases}\frac\pi3&\text{for }|x|\le\frac\pi3\\0&\text{for }\frac\pi3$

and enforcing a period of $2L=2\pi$ . Now, you should find that

$\varphi(x)\sim\dfrac2{\sqrt3}\left(\cos x-\dfrac{\cos5x}5+\dfrac{\cos7x}7-\dfrac{\cos11x}{11}+\cdots\right)$

The value of the sum can then be verified by choosing $x=0$ , which gives

$\varphi(0)=\dfrac\pi3=\dfrac2{\sqrt3}\left(1-\dfrac15+\dfrac17-\dfrac1{11}+\cdots\right)$
$\implies\dfrac\pi{2\sqrt3}=1-\dfrac15+\dfrac17-\dfrac1{11}+\cdots$

as required.

5 0

3 years ago

Given the trinomial, what is the value of the coefficient B in the factored form?

Ivenika [448]

Answer:

B = 6

Step-by-step explanation:

2x^2 + 4xy − 48y^2

Factor out 2

2(x^2 + 2xy − 24y^2)

What 2 numbers multiply to -24 and add to 2

-4 *6 = -24

-4+6 = 2

2 ( x+6y)( x-4y)

8 0

2 years ago

Read 2 more answers

Can someone please help

leonid [27]

Answers:

Lateral Area = No lateral area (choice D)
Surface Area = 25.97 square inches (choice E)
Volume = 12.44 cubic inches (choice A)

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Explanation:

Lateral area only applies to prisms and cylinders. Spheres do not have lateral sides, so there is no lateral area.

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The radius is 1 & 7/16

Let's convert this to decimal form

1 & 7/16 = 1 + (7/16)

1 & 7/16 = 1 + 0.4375

1 & 7/16 = 1.4375

The radius is r = 1.4375 inches.

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

SA = Surface area the sphere

SA = 4*pi*r^2

SA = 4*pi*(1.4375)^2

SA = 25.9672267773281

SA = 25.97 square inches (choice E)

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

V = Volume of the sphere

V = (4/3)*pi*r^3

V = (4/3)*pi*(1.4375)^3

V = 12.4426294974698

V = 12.44 cubic inches (choice A)

8 0

3 years ago

Find the angle of this sector. <br>on the image

KatRina [158]

Answer:

$\alpha =107.4^{o}$

Step-by-step explanation:

$15=\frac{\pi (8)\alpha }{180}$

$\alpha =\frac{(15)(180)}{8\pi } =\frac{2700}{25.13}=107.4$

Hope this helps

5 0

2 years ago

Read 2 more answers

Karla's starting salary was $32,000.She gets a 700 raise every year. Write an equation that models this.

julsineya [31]

Answer:

Y=year

y=700+32,000

6 0

2 years ago