Are you interesting about average value if so trying here.

memomath
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Hello

here you have the same question in the enclosed

What is the average value?

average value for (exp \alphaZ ) = \int\int exp\alphaZ ds / \int\int ds



Over the sphere S: X^2+Y^2+Z^2=a^2

Also by use the parameterization

X= a sinϴ cos ɸ
Y= a sinϴ sin ɸ
Z= a cos ϴ

And the usual substitution t = cos ϴ in the integral:

0\int\Pi f (cos ϴ) sinϴ dϴ =-1\int1 f(t) dt

Thanks
 
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memomath said:
hello

please open the enclosed to find a nice problem and to solve this interesting question

thanks
 
Again, Word files are notorious for harboring viruses. I will not open one from someone I do not know.
 
Hello here the same question in the enclosed

What is the average value?

average value for (exp \alphaZ ) = \int\int exp\alphaZ ds / \int\int ds



Over the sphere S: X^2+Y^2+Z^2=a^2

Also by use the parameterization

X= a sinϴ cos ɸ
Y= a sinϴ sin ɸ
Z= a cos ϴ

And the usual substitution t = cos ϴ in the integral:

0\int\Pi f (cos ϴ) sinϴ dϴ =-1\int1 f(t) dt

Thanks
 
I can kind of guess what you mean, but your notation is pretty bad. I do not know what exp\:^\alpha Z is supposed to be. Your substitution seems wrong, your notation is unorthodox and you write factors like -1 instead of just a - . This is probably the reason why people don't answer.

You might have better chances if you wrote something like:

"I am trying to get the average \left< f(z) \right>_{S_a} of a function f(z)= \alpha ^ z over a sphere S_a of radius r=\sqrt{a}. I swear this is not for homework.

What I have so far is this:

\left< f(z) \right>_{S_a} = \frac{\int_{S_a} \alpha^z\,\mathrm{d}\Omega}{\int_{S_a} \,\mathrm{d}\Omega}

I tried to express the integral in polar coordinates:
X= a sinϴ cos ɸ
Y= a sinϴ sin ɸ
Z= a cos ϴ
\theta \in \left[0,\pi \right]
\phi \in \left[0,2\pi \right]

and found:
\int_{S_a} f(z) \,\mathrm{d}\Omega = \int_0^{\pi} f(\cos \theta) \sin \theta \, \mathrm{d}\theta

Is this correct? How do I proceed?"

Then people would have told you what you did wrong.
 
Thanks for reply but it is not correct hint and I think you don’t proceed with the right way for the real problem you probably fix some thing else many things missing from the real posted thank you
0xDEADBEEF said:
I can kind of guess what you mean, but your notation is pretty bad. I do not know what exp\:^\alpha Z is supposed to be. Your substitution seems wrong, your notation is unorthodox and you write factors like -1 instead of just a - . This is probably the reason why people don't answer.

You might have better chances if you wrote something like:

"I am trying to get the average \left< f(z) \right>_{S_a} of a function f(z)= \alpha ^ z over a sphere S_a of radius r=\sqrt{a}. I swear this is not for homework.

What I have so far is this:

\left< f(z) \right>_{S_a} = \frac{\int_{S_a} \alpha^z\,\mathrm{d}\Omega}{\int_{S_a} \,\mathrm{d}\Omega}

I tried to express the integral in polar coordinates:
X= a sinϴ cos ɸ
Y= a sinϴ sin ɸ
Z= a cos ϴ
\theta \in \left[0,\pi \right]
\phi \in \left[0,2\pi \right]

and found:
\int_{S_a} f(z) \,\mathrm{d}\Omega = \int_0^{\pi} f(\cos \theta) \sin \theta \, \mathrm{d}\theta

Is this correct? How do I proceed?"

Then people would have told you what you did wrong.
 
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YES memomath I believe there are some mistakes and the good hint to the correct answer for this problem would be in ENGINEERING MATHEMATICS JOHN BIRD

memomath said:
Thanks for reply but it is not correct hint and I think you don’t proceed with the right way for the real problem you probably fix some thing else many things missing from the real posted thank you
 
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