How to calculate this n dimensional integral?

Clash Royale CLAN TAG#URR8PPP
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The integral such as
It's easy to evaluate the first few items
Integrate[x1 (1/(-1+n))^n (1/v1)^(n/(-1+n)) x1^((2-n)/(-1+n)), x1, 0, v1]
Integrate[x1 Integrate[(1/(-1+n))^n (1/v1)^(n/(-1+n)) x1^((2-n)/(-1+n)) x2^((2-n)/(-1+n)), x2, 0, x1], x1, 0, v1]
Integrate[x1 Integrate[Integrate[(1/(-1+n))^n (1/v1)^(n/(-1+n)) x1^((2-n)/(-1+n)) x2^((2-n)/(-1+n)) x3^((2-n)/(-1+n)), x3, 0, x1], x2, 0, x1], x1, 0, v1]
but how do I calculate this integral where the number of integrals is aribtrary?
calculus-and-analysis
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up vote
2
down vote
favorite
The integral such as
It's easy to evaluate the first few items
Integrate[x1 (1/(-1+n))^n (1/v1)^(n/(-1+n)) x1^((2-n)/(-1+n)), x1, 0, v1]
Integrate[x1 Integrate[(1/(-1+n))^n (1/v1)^(n/(-1+n)) x1^((2-n)/(-1+n)) x2^((2-n)/(-1+n)), x2, 0, x1], x1, 0, v1]
Integrate[x1 Integrate[Integrate[(1/(-1+n))^n (1/v1)^(n/(-1+n)) x1^((2-n)/(-1+n)) x2^((2-n)/(-1+n)) x3^((2-n)/(-1+n)), x3, 0, x1], x2, 0, x1], x1, 0, v1]
but how do I calculate this integral where the number of integrals is aribtrary?
calculus-and-analysis
Isn't this quantity just equal to$$ I = left( frac1n-1 right)^n nu_1^-n/(n-1) int_0^nu_1 x_1 x_1^(2-n)/(n-1) left[ int_0^x_1 y^(2-n)/(n-1) dy right]^n-1 , dx_1 ? $$
â Michael Seifert
1 hour ago
add a comment |Â
up vote
2
down vote
favorite
up vote
2
down vote
favorite
The integral such as
It's easy to evaluate the first few items
Integrate[x1 (1/(-1+n))^n (1/v1)^(n/(-1+n)) x1^((2-n)/(-1+n)), x1, 0, v1]
Integrate[x1 Integrate[(1/(-1+n))^n (1/v1)^(n/(-1+n)) x1^((2-n)/(-1+n)) x2^((2-n)/(-1+n)), x2, 0, x1], x1, 0, v1]
Integrate[x1 Integrate[Integrate[(1/(-1+n))^n (1/v1)^(n/(-1+n)) x1^((2-n)/(-1+n)) x2^((2-n)/(-1+n)) x3^((2-n)/(-1+n)), x3, 0, x1], x2, 0, x1], x1, 0, v1]
but how do I calculate this integral where the number of integrals is aribtrary?
calculus-and-analysis
The integral such as
It's easy to evaluate the first few items
Integrate[x1 (1/(-1+n))^n (1/v1)^(n/(-1+n)) x1^((2-n)/(-1+n)), x1, 0, v1]
Integrate[x1 Integrate[(1/(-1+n))^n (1/v1)^(n/(-1+n)) x1^((2-n)/(-1+n)) x2^((2-n)/(-1+n)), x2, 0, x1], x1, 0, v1]
Integrate[x1 Integrate[Integrate[(1/(-1+n))^n (1/v1)^(n/(-1+n)) x1^((2-n)/(-1+n)) x2^((2-n)/(-1+n)) x3^((2-n)/(-1+n)), x3, 0, x1], x2, 0, x1], x1, 0, v1]
but how do I calculate this integral where the number of integrals is aribtrary?
calculus-and-analysis
calculus-and-analysis
asked 1 hour ago
mathe
2,59811643
2,59811643
Isn't this quantity just equal to$$ I = left( frac1n-1 right)^n nu_1^-n/(n-1) int_0^nu_1 x_1 x_1^(2-n)/(n-1) left[ int_0^x_1 y^(2-n)/(n-1) dy right]^n-1 , dx_1 ? $$
â Michael Seifert
1 hour ago
add a comment |Â
Isn't this quantity just equal to$$ I = left( frac1n-1 right)^n nu_1^-n/(n-1) int_0^nu_1 x_1 x_1^(2-n)/(n-1) left[ int_0^x_1 y^(2-n)/(n-1) dy right]^n-1 , dx_1 ? $$
â Michael Seifert
1 hour ago
Isn't this quantity just equal to$$ I = left( frac1n-1 right)^n nu_1^-n/(n-1) int_0^nu_1 x_1 x_1^(2-n)/(n-1) left[ int_0^x_1 y^(2-n)/(n-1) dy right]^n-1 , dx_1 ? $$
â Michael Seifert
1 hour ago
Isn't this quantity just equal to$$ I = left( frac1n-1 right)^n nu_1^-n/(n-1) int_0^nu_1 x_1 x_1^(2-n)/(n-1) left[ int_0^x_1 y^(2-n)/(n-1) dy right]^n-1 , dx_1 ? $$
â Michael Seifert
1 hour ago
add a comment |Â
1 Answer
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Your integral is equal to
$$
I = left( frac1n-1 right)^n nu_1^-n/(n-1) int_0^nu_1 left x_1 x_1^(2-n)/(n-1) left[ int_0^x_1 y^(2-n)/(n-1) dy right]^n-1 , right dx_1,
$$
which is easy enough to solve for in Mathematica. Note that we must have $n > 1$ for convergence, and things simplify nicely if we assume that $nu_1 > 0$ as well.
subint[x1_, n_] = Integrate[y^((2 - n)/(n - 1)), y, 0, x1, Assumptions -> n > 1]
int[[Nu]1_, n_] = Simplify[(1/(n - 1))^n [Nu]1^(-n/(n - 1))
Integrate[ x1^((2 - n)/(n - 1) + 1) subint[x1, n]^(n - 1), x1, 0, [Nu]1], Assumptions -> n > 1, [Nu]1 > 0]
(* [Nu]1/(-1 + 2 n) *)
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
5
down vote
Your integral is equal to
$$
I = left( frac1n-1 right)^n nu_1^-n/(n-1) int_0^nu_1 left x_1 x_1^(2-n)/(n-1) left[ int_0^x_1 y^(2-n)/(n-1) dy right]^n-1 , right dx_1,
$$
which is easy enough to solve for in Mathematica. Note that we must have $n > 1$ for convergence, and things simplify nicely if we assume that $nu_1 > 0$ as well.
subint[x1_, n_] = Integrate[y^((2 - n)/(n - 1)), y, 0, x1, Assumptions -> n > 1]
int[[Nu]1_, n_] = Simplify[(1/(n - 1))^n [Nu]1^(-n/(n - 1))
Integrate[ x1^((2 - n)/(n - 1) + 1) subint[x1, n]^(n - 1), x1, 0, [Nu]1], Assumptions -> n > 1, [Nu]1 > 0]
(* [Nu]1/(-1 + 2 n) *)
add a comment |Â
up vote
5
down vote
Your integral is equal to
$$
I = left( frac1n-1 right)^n nu_1^-n/(n-1) int_0^nu_1 left x_1 x_1^(2-n)/(n-1) left[ int_0^x_1 y^(2-n)/(n-1) dy right]^n-1 , right dx_1,
$$
which is easy enough to solve for in Mathematica. Note that we must have $n > 1$ for convergence, and things simplify nicely if we assume that $nu_1 > 0$ as well.
subint[x1_, n_] = Integrate[y^((2 - n)/(n - 1)), y, 0, x1, Assumptions -> n > 1]
int[[Nu]1_, n_] = Simplify[(1/(n - 1))^n [Nu]1^(-n/(n - 1))
Integrate[ x1^((2 - n)/(n - 1) + 1) subint[x1, n]^(n - 1), x1, 0, [Nu]1], Assumptions -> n > 1, [Nu]1 > 0]
(* [Nu]1/(-1 + 2 n) *)
add a comment |Â
up vote
5
down vote
up vote
5
down vote
Your integral is equal to
$$
I = left( frac1n-1 right)^n nu_1^-n/(n-1) int_0^nu_1 left x_1 x_1^(2-n)/(n-1) left[ int_0^x_1 y^(2-n)/(n-1) dy right]^n-1 , right dx_1,
$$
which is easy enough to solve for in Mathematica. Note that we must have $n > 1$ for convergence, and things simplify nicely if we assume that $nu_1 > 0$ as well.
subint[x1_, n_] = Integrate[y^((2 - n)/(n - 1)), y, 0, x1, Assumptions -> n > 1]
int[[Nu]1_, n_] = Simplify[(1/(n - 1))^n [Nu]1^(-n/(n - 1))
Integrate[ x1^((2 - n)/(n - 1) + 1) subint[x1, n]^(n - 1), x1, 0, [Nu]1], Assumptions -> n > 1, [Nu]1 > 0]
(* [Nu]1/(-1 + 2 n) *)
Your integral is equal to
$$
I = left( frac1n-1 right)^n nu_1^-n/(n-1) int_0^nu_1 left x_1 x_1^(2-n)/(n-1) left[ int_0^x_1 y^(2-n)/(n-1) dy right]^n-1 , right dx_1,
$$
which is easy enough to solve for in Mathematica. Note that we must have $n > 1$ for convergence, and things simplify nicely if we assume that $nu_1 > 0$ as well.
subint[x1_, n_] = Integrate[y^((2 - n)/(n - 1)), y, 0, x1, Assumptions -> n > 1]
int[[Nu]1_, n_] = Simplify[(1/(n - 1))^n [Nu]1^(-n/(n - 1))
Integrate[ x1^((2 - n)/(n - 1) + 1) subint[x1, n]^(n - 1), x1, 0, [Nu]1], Assumptions -> n > 1, [Nu]1 > 0]
(* [Nu]1/(-1 + 2 n) *)
answered 1 hour ago
Michael Seifert
6,8391341
6,8391341
add a comment |Â
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Isn't this quantity just equal to$$ I = left( frac1n-1 right)^n nu_1^-n/(n-1) int_0^nu_1 x_1 x_1^(2-n)/(n-1) left[ int_0^x_1 y^(2-n)/(n-1) dy right]^n-1 , dx_1 ? $$
â Michael Seifert
1 hour ago