| (1):∫_0 ^1 K(k)^3 dk=(1/8)∫∫∫_([0,1]^3 ) u_1 ^(−(1/2)) u_2 ^(−(1/2)) u_3 ^(−(1/2)) (1−u_1 )^(−(1/2)) (1−u_2 )^(−(1/2)) (1−u_3 )^(−(( 1)/2)) (∫_0 ^1 Π_(i=1) ^3 (1−k^2 u_i )^(−(1/2)) dk)du_1 du_2 du_3
=(1/(16))Σ_(n_1 =0) ^∞ Σ_(n_2 =0) ^∞ Σ_(n_3 =0) ^∞ (((2n_1 )),(n_1 ) ) (((2n_2 )),(n_2 ) ) (((2n_3 )),(n_3 ) )(1/(4^(n_1 +n_2 +n_3 ) (n_1 +n_2 +n_3 +(1/2))))∫∫∫_([0,1]^3 ) Π_(i=1) ^3 u_i ^(n_i −(1/2)) (1−u_i )^(−(1/2)) du_1 du_2 du_3
=(1/(16))Σ_(n_1 =0) ^∞ Σ_(n_2 =0) ^∞ Σ_(n_3 =0) ^∞ (((2n_1 )),(n_1 ) ) (((2n_2 )),(n_2 ) ) (((2n_3 )),(n_3 ) )(1/(4^(n_1 +n_2 +n_3 ) (n_1 +n_2 +n_3 +(1/2))))Π_(i=1) ^3 ∫_0 ^1 u_i ^(n_i −(1/2)) (1−u_i )^(−(1/2)) du_i
=(1/(16))Σ_(n_1 =0) ^∞ Σ_(n_2 =0) ^∞ Σ_(n_3 =0) ^∞ (((2n_1 )),(n_1 ) ) (((2n_2 )),(n_2 ) ) (((2n_3 )),(n_3 ) )(1/(4^(n_1 +n_2 +n_3 ) (n_1 +n_2 +n_3 +(1/2))))Π_(i=1) ^3 (((2n_i )),(n_i ) )(π/4^n_i )
=(1/(16))π^3 Σ_(n_1 =0) ^∞ Σ_(n_2 =0) ^∞ Σ_(n_3 =0) ^∞ ((Π_(i=1) ^3 (((2n_i )),(n_i ) )^2 )/(16^(n_1 +n_2 +n_3 ) (n_(1 ) +n_2 +n_3 +(1/2))))
=((3Γ((1/4))^8 )/(1280π^3 ))
(2):K(k)=(π/2)Σ_(n=0) ^∞ ((((2n)!)/(2^(2n) (n!)^2 )))^2 k^(2n)
K(k)^3 =((π/2))^3 Σ_(n,m,p=0) ^∞ ((((2n)!(2m)!(2p)!)/(2^(2(n+m+p)) (n!m!p!)^2 )))^2 k^(2(n+m+p))
∫_0 ^1 K(k)^3 dk=((π/2))^3 Σ_(n,m,p=0) ^∞ ((((2n)!(2m)!(2p)!)/(2^(2(n+m+p)) (n!m!p!)^2 )))^2 (1/(2(n+m+p)+1))
Σ_(n,m,p=0) ^∞ (((2n)!(2m)!(2p)!)/((n!m!p!)^2 )) (x^(n+m+p) /(2(n+m+p)+1))=(3/5) _4 F_3 ((1/2),(1/2),(1/2),(1/2);1,1,1;16x)
∵x=(1/(16))⇒ _4 F_3 ((1/2),(1/2),(1/2),(1/2);1,1,1;1)=((Γ((1/4))^8 )/(128π^6 ))
∴∫_0 ^1 K(k)^3 dk=((3π^3 )/(1280))∙((Γ((1/4))^8 )/π^6 )=((3Γ((1/4))^8 )/(1280π^3 ))
(1)∫_0 ^1 k^(1/3) (1−k^2 )^(−1/3) K(k)^2 dk
k=sinθ⇒dk=cosθdθ
∫_(0 ) ^(π/2) sin^(1/3) θ(1−sin^2 θ)^(−1/3) cosθK(sin θ)^2 dθ
=∫_0 ^(π/2) sin^(1/3) θ cos^(−2/3) θ K(sin θ)^2 dθ
K(k)=(π/2)Σ_(n=0) ^∞ ((((1/2))_n ^2 )/((n!)^2 ))k^(2n)
K(k)^2 =((π/2))^2 Σ_(m,n=0) ^∞ ((((1/2))_m ^2 ((1/2))_n ^2 )/((m!)(n!)^2 ))k^(2(m+n))
∫_0 ^(π/2) sin^(1/3+2(m+n)) θ cos^(−2/3) θ dθ=(1/2)B((2/3)+m+n,(1/6))
=(1/2) ((Γ((2/3)+m+n)Γ((1/6)))/(Γ((5/6)+m+n)))
Σ_(m,n=0) ^∞ ((((1/2))_m ^2 ((1/2))_n ^2 )/((m!)^2 (n!)^2 )) ((Γ((2/3)+m+n)Γ((1/6)))/(2Γ((5/6)+m+n)))
=((Γ((1/6)))/2)Σ_(k=0) ^∞ ((Γ((2/3)+k))/(Γ((5/6)+k)))Σ_(m+n=k) ((((1/2))_m ^2 ((1/2))_n ^2 )/((m!)^2 (n!)^2 ))
=((Γ((1/6)))/2)Σ_(k=0) ^∞ ((Γ((2/3)+k))/(Γ((5/6)+k))) ((((1/2))_k ^2 )/((k!)^2 )) (((2k)),(k) )
=((Γ((1/6)))/2)Σ_(k=0) ^∞ ((Γ((2/3)+k)Γ((1/2)+k)((1/2))_k )/(Γ((5/6)+k)Γ(1+k))) ((((1/2))_k )/(k!))
=((Γ((1/6)))/2) ((Γ((2/3))Γ((1/2)))/(Γ((5/6))))F_2 ((2/3),(1/2),(1/2);(5/6),1;1)
=((Γ((1/6))Γ((2/3))Γ((1/2)))/(2Γ((5/6)))) ((Γ((5/6))Γ((1/6)))/(Γ((1/2))Γ((2/3))))=((Γ((1/6))^2 )/2)
(π^2 /4) ((Γ((1/6))^2 )/2)=((π^2 Γ((1/6))^2 )/8)
“(((√3)Γ((1/3))^9 )/(64(2)^(1/3) π^3 ))”=((π^2 Γ((1/6))^2 )/8)⇒Γ((1/6))=(((√3)Γ((1/3))^(9/2) )/(8(2)^(1/6) π^(5/2) ))
(2):Γ((2/3))≜((2π)/( (√3)Γ((1/3))))
K(k)=(π/2) _2 F_1 ((1/2),(1/2);1;k^2 )
K(k)^2 =((π/2))^2 Σ_(m=0) ^∞ Σ_(n=0) ^∞ ((((1/2))_m ((1/2))_n ((1/2))_m ((1/2))_n )/(m!n!m!n!))k^(2(m+n))
((1/2))_m = (((2m)),(m) )(1/4^m ) ∀m∈N
K(k)^2 =(π^4 /4)Σ_(p=0) ^∞ (((2p)),(p) )(k^(2p) /(16^p ))Σ_(q=0) ^p (((2q)),(q) )^2 (((2(p−q))),((p−q)) )( (((2p)),(p) )^2 /( (((2q)),(q) )^2 (((2(p−q))),((p−q)) )^2 ))
c_p ≜Σ_(p=0) ^p (((2q)),(q) )^2 (((2(p−q))),((p−q)) )^2
K(k)^2 =(π^2 /4)Σ_(p=0) ^∞ c_p (k^(2p) /(16^p ))
∫_0 ^1 k^(1/3) (1−k^2 )^(−(1/3)) K(k)^2 dk=(π^2 /4)Σ_(p=0) ^∞ c_p (1/(16^p ))∫_0 ^1 k^(1/3) (1−k^2 )^(−(1/3)) k^(2p) dk
u≜k^2 ⇒dk=(1/2)u^(−(1/2)) du
∫_0 ^1 k^((1/3)+2p) (1−k^2 )^(−(1/3)) dk=(1/2)∫_0 ^1 u^((1/6)+p) (1−u)^(−(1/3)) u^(−(1/2)) du=(1/2)∫_0 ^1 u^(p−(1/3)) (1−u)^(−(1/3)) du
∫_0 ^1 u^(a−1) (1−u)^(b−1) du=B(a,b) for a>0,b
a≜p+(2/3),b≜(2/3)
B(p+(2/3),(2/3))=∫_0 ^1 u^(p+(2/3)−1) (1−u)^((2/3)−1) du
Γ(p+(3/4))=(p+(2/3))Γ(p+(2/3))
B(p+(2/3),(2/3))=((Γ(p+(2/3))Γ((2/3)))/(Γ(p+(3/4))))=((Γ(p+(2/3))Γ((2/3)))/((p+(2/3))(p+(2/3))))=((Γ((2/3)))/(p+(2/3)))
∫_0 ^1 k^((1/3)+2p) (1−k^2 )^(−(1/3)) dk=(1/2) ((Γ((2/3)))/(p+(2/3)))
∫_0 ^1 k^(1/3) (1−k^2 )^(−(1/2)) K(k)^2 dk=(π^2 /4)Σ_(p=0) ^∞ c_p (1/(16^p )) (1/2) ((Γ((2/3)))/(p+(2/3)))=(π^2 /8)Γ((2/3))Σ_(p=0) ^∞ c_p (1/(16^p )) (1/(p+(2/3)))
(1/(p+(2/3)))=∫_0 ^1 v^(p+(2/3)−1) dv ∀p∈N
Σ_(p=0) ^∞ c_p ((1/(16)))^p (1/(p+(2/3)))=∫_0 ^1 v^((2/3)−1) Σ_(p=0) ^∞ c_p ((v/(16)))^p dv
Σ_(p=0) ^∞ c_p w^p =(Σ_(p=0) ^∞ (((2n)),(n) )^2 w^n )=( _2 F_1 ((1/2),(1/2);1;16w))^2
Σ_(p=0) ^∞ c_(p ) ((1/(16)))^p +(1/(p+(2/3)))=∫_0 ^1 v^((2/3)−1) ( _2 F_1 ((1/2);(1/2);1;16∙(v/(16))))^2 dv=∫_0 ^1 v^((2/3)−1) ( _2 F_1 ((1/2),(1/2);1;v))^2 dv
_2 F_1 ((1/2),(1/2);1,v)=(2/π)K((√v))^2
Σ_(p=0) ^∞ c_p ((1/(16)))^p (1/(p+(2/3)))=∫_0 ^1 v^((2/3)−1) (4/π^2 )K((√v))^2 dv
t≜(√v)⇒v=t^2 ⇒dv=2tdt
∫_0 ^1 v^((2/3)−1) K((√v))^2 dv=∫_0 ^1 (t^2 )^((2/3)−1) K(t)^2 2tdt=2∫_0 ^1 t^((4/3)−2) −K(t)^2 tdt=2∫_0 ^1 t^(1/3) K(t)^2 dt
Σ_(p=0) ^∞ c_p ((1/(16)))^p (1/(p+(2/3)))=(4/π^2 )∙2∫_0 ^1 t^(1/3) K(t)^2 dt=(8/π^2 )∫_0 ^1 t^(1/3) K(t)^2 dt
∫_0 ^1 k^(1/3) (1−k^2 )^(−(1/3)) K(k)^2 dk=(π^2 /8)Γ((3/8))∙(8/π^2 )∫_0 ^1 t^(1/3) K(t)^2 dt=Γ((2/3))∫_0 ^1 t^(1/3) K(t)^2 dt
∫_0 ^1 t^(1/3) K(t)^2 dt=∫_0 ^1 t^(1/3) (1−t^2 )^(−(1/3)) K(t)^2 dt
(1−t^2 )^(−(1/3)) =Γ((3/4))((Γ((2/3)))/(Γ((2/3))))(1−t^2 )^(−(1/3))
∫_(0 ) ^1 t^(1/3) (1−t^2 )^(−(1/3)) K(t)^2 dt=Γ((2/3))∫_0 ^1 t^(1/3) K(t)^2 dt
Γ((2/3))∫_0 ^1 t^(1/3) K(t)^2 dt=Γ((2/3))∙((Γ((2/3)))/(Γ((2/3))))∫_0 ^1 t^(1/3) K(t)^2 dt
∫_0 ^∞ (t^(α−1) /(t^π +1))=(1/(sin α)) For 0<α<π
Γ((1/3))^3 =(2/π)Γ((1/3))^3 π=2(√3)Γ((1/3))^2 Γ((1/3))(π/(2Γ((1/3))))
Γ((1/3))Γ((2/3))=((2π)/( (√3)))
Γ((1/9))^9 =Γ((1/3))^9
(((√3)Γ((1/3))^9 )/(64(2)^(1/3) π^3 ))=((Γ((1/9))^9 Γ((1/3))Γ((2/3))sin((π/3)))/(64(2)^(1/3) π^3 )) ((Γ((1/3))Γ((2/3)))/(Γ((1/3))Γ((2/3))))π
((Γ((1/3))^9 Γ((1/3))Γ((2/3))((√3)/2))/(64(2)^(1/3) π^3 π)) ((Γ((1/3))Γ((2/3)))/(Γ((1/3))Γ((2/3))))
((Γ((1/3))^9 Γ((1/3))Γ((2/3)))/(128(2)^(1/8) π^4 Γ((1/3))Γ((2/3)))) ((√3)/2)=((Γ((1/3))^9 (√3))/(256(2)^(1/3) π^4 ))
=(((√3)Γ((1/3))^9 )/(64(2)^(1/3) π^3 ))
∫_0 ^(π/2) ((x((tan x))^(1/4) )/(sin x))dx=(((3−2(√2)))/(24))Γ((1/8))Γ((3/8))
(1):I=∫_0 ^(π/2) ((x tan^(1/4) x)/(sin x))dx=∫_0 ^(π/2) x tan^(−3/4) x sec x dx
tan x=t⇒dx=(dt/(1+t^2 )),sec x=(√(1+t^2 ))
I=∫_0 ^∞ ((arctant∙t^(−3/4) )/( (√(1+t^2 ))))dt
arctan t=∫_0 ^1 (t/(1+y^2 t^2 ))dy
I=∫_0 ^1 ∫_0 ^∞ (t^(1/4) /((1+y^2 t^2 )(√(1+t^2 ))))dt dy
t=(u/y)⇒dt=(du/y),t^2 =(u^2 /y^2 )
I=∫_0 ^1 y^(−5/4) ∫_0 ^∞ (u^(1/4) /((1+u^2 )(√(1+(u^2 /y^2 )))))du dy
(√(1+(u^2 /y^2 )))=(√((y^2 +u^2 )/y))
I=∫_0 ^1 y^(−1/4) ∫_0 ^∞ (u^(1/4) /((1+u^2 )(√(y^2 +u^2 ))))du dy
∫_0 ^∞ (u^(1/4) /((1+u^2 )(√(y^2 +u^2 ))))dx=(π/(2(√(y^2 −1))))(y^(−1/4) −y^(5/4) )
I=(π/2)∫_0 ^1 ((y^(−1/4) −y^(−5/4) )/( (√(y^2 −1))))dy
y=sinθ⇒dy=cos θ dθ
I=(π/2)∫_0 ^(π/2) ((sin^(−1/4) θ−sin^(5/4) θ)/( (√(sin θ−1))))cos θ dθ
(√(sin^2 θ−1))=i cos θ
I=(π/(2i))∫_0 ^(π/2) (sin^(−1/4) θ−sin^(−5/4) θ)dθ
I=(π/(2i))∫_0 ^(π/2) (sin^(−1/4) −sin^(−5/4) θ)dθ
∫_0 ^(π/2) sin^a θ dθ=(((√π)Γ(((a+1)/2)))/(2Γ((a/2)+1)))
I=(π/(2i))[(((√π)Γ((3/8)))/(2Γ((7/8))))−(((√π)Γ(−(1/8)))/(2Γ((3/8))))]
Γ((7/8))Γ((1/8))=(π/(sin(π/8))),Γ(−(1/8))=−(8/7)Γ((7/8))
I=(π^(3/2) /(4i))[((Γ((3/8))Γ((1/8)))/π)sin(π/8)+((8Γ((7/8))Γ((3/8)))/(7Γ((3/8))))]
sin(π/8)=((√(2−(√2)))/2)
I=(π^(3/2) /(4i))[((Γ((3/8))Γ((1/8)))/π)∙((√(2−(√2)))/2)+((8Γ((7/8)))/7)]
Γ((7/8))=(π/(Γ((1/8))sin(π/8)))
I=(π^(3/2) /(4i))[((Γ((3/8))Γ((1/8)))/π)∙((√(2−(√2)))/2)+((8π)/(7Γ((1/8))sin(π/8)))]
Γ((3/8))Γ((5/4))=(π/(sin((3π)/8))),sin((3π)/8)=((√(2+(√2)))/2)
=(((3−2(√2)))/(24))Γ((1/8))Γ((3/8))
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