55 HFOPDE, chapter 2.6.4

55.1 problem number 1
55.2 problem number 2
55.3 problem number 3
55.4 problem number 4
55.5 problem number 5
55.6 problem number 6
55.7 problem number 7
55.8 problem number 8
55.9 problem number 9
55.10 problem number 10
55.11 problem number 11
55.12 problem number 12

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55.1 problem number 1

problem number 489

Added January 20, 2019.

Problem 2.6.4.1 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\)

\[ w_x + \left ( a \cot ^k(\lambda x)+b \right ) w_y = 0 \]

Mathematica

ClearAll[w, x, y, n, a, b, m, c, k, alpha, beta, gamma, A, C0, s, lambda, B, s, mu, d, g, B]; 
 pde = D[w[x, y], x] + (a*Cot[lambda*x]^k + b)*D[w[x, y], y] == 0; 
 sol = AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

\[ \left \{\left \{w(x,y)\to c_1\left (-\frac {-a \cot ^{k+1}(\lambda x) \text {Hypergeometric2F1}\left (1,\frac {k+1}{2},\frac {k+1}{2}+1,-\cot ^2(\lambda x)\right )+b k \lambda x+b \lambda x-k \lambda y-\lambda y}{(k+1) \lambda }\right )\right \}\right \} \]

Maple

 
w:='w';x:='x';y:='y';a:='a';b:='b';n:='n';m:='m';c:='c';k:='k';alpha:='alpha';beta:='beta';g:='g';A:='A'; C:='C';lambda:='lambda';B:='B';mu:='mu';d:='d';s:='s'; 
pde :=   diff(w(x,y),x)+  (a*cot(lambda*x)^k+b)*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[ w \left ( x,y \right ) ={\it \_F1} \left ( -bx+y-\int \!a \left ( \cot \left ( \lambda \,x \right ) \right ) ^{k}\,{\rm d}x \right ) \] Has unresolved integral

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55.2 problem number 2

problem number 490

Added January 20, 2019.

Problem 2.6.4.2 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\)

\[ w_x + \left ( a \cot ^k(\lambda y)+b \right ) w_y = 0 \]

Mathematica

ClearAll[w, x, y, n, a, b, m, c, k, alpha, beta, gamma, A, C0, s, lambda, B, s, mu, d, g, B]; 
 pde = D[w[x, y], x] + (a*Cot[lambda*y]^k + b)*D[w[x, y], y] == 0; 
 sol = AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

\[ \left \{\left \{w(x,y)\to c_1\left (\int _1^y \frac {1}{a \cot ^k(\lambda K[1])+b} \, dK[1]-x\right )\right \}\right \} \]

Maple

 
w:='w';x:='x';y:='y';a:='a';b:='b';n:='n';m:='m';c:='c';k:='k';alpha:='alpha';beta:='beta';g:='g';A:='A'; C:='C';lambda:='lambda';B:='B';mu:='mu';d:='d';s:='s'; 
pde :=   diff(w(x,y),x)+  (a*cot(lambda*y)^k+b)*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[ w \left ( x,y \right ) ={\it \_F1} \left ( -\int \! \left ( a \left ( \cot \left ( y\lambda \right ) \right ) ^{k}+b \right ) ^{-1}\,{\rm d}y+x \right ) \]

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55.3 problem number 3

problem number 491

Added January 20, 2019.

Problem 2.6.4.3 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\)

\[ w_x + a \cot ^k(x+\lambda y) w_y = 0 \]

Mathematica

ClearAll[w, x, y, n, a, b, m, c, k, alpha, beta, gamma, A, C0, s, lambda, B, s, mu, d, g, B]; 
 pde = D[w[x, y], x] + a*Cot[x + lambda*y]^k*D[w[x, y], y] == 0; 
 sol = AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

\[ \text {\$Aborted} \] Timed out

Maple

 
w:='w';x:='x';y:='y';a:='a';b:='b';n:='n';m:='m';c:='c';k:='k';alpha:='alpha';beta:='beta';g:='g';A:='A'; C:='C';lambda:='lambda';B:='B';mu:='mu';d:='d';s:='s'; 
pde :=   diff(w(x,y),x)+  cot(x+lambda*y)^k*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[ w \left ( x,y \right ) ={\it \_F1} \left ( -\int ^{{\frac {y\lambda +x}{\lambda }}}\! \left ( 1+ \left ( \cot \left ( \lambda \,{\it \_a} \right ) \right ) ^{k}\lambda \right ) ^{-1}{d{\it \_a}}\lambda +x \right ) \]

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55.4 problem number 4

problem number 492

Added January 20, 2019.

Problem 2.6.4.4 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\)

\[ w_x + \left ( y^2+a \lambda + a(\lambda -a) \cot ^2(\lambda x) \right ) w_y = 0 \]

Mathematica

ClearAll[w, x, y, n, a, b, m, c, k, alpha, beta, gamma, A, C0, s, lambda, B, s, mu, d, g, B]; 
 pde = D[w[x, y], x] + (y^2 + a*lambda + a*(lambda - a)*Cot[lambda*x]^2)*D[w[x, y], y] == 0; 
 sol = AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

\[ \text {Failed} \]

Maple

 
w:='w';x:='x';y:='y';a:='a';b:='b';n:='n';m:='m';c:='c';k:='k';alpha:='alpha';beta:='beta';g:='g';A:='A'; C:='C';lambda:='lambda';B:='B';mu:='mu';d:='d';s:='s'; 
pde :=   diff(w(x,y),x)+ ( y^2+a*lambda + a*(lambda-a)*cot(lambda*x)^2  )*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[ w \left ( x,y \right ) ={\it \_F1} \left ( -{1 \left ( \LegendreP \left ( 1/2\,{\frac {2\,a-\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) a\cos \left ( 3\,\lambda \,x \right ) +3\,\sin \left ( \lambda \,x \right ) \LegendreP \left ( 1/2\,{\frac {2\,a-\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) y-\cos \left ( \lambda \,x \right ) \LegendreP \left ( 1/2\,{\frac {2\,a-\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) a-\sin \left ( 3\,\lambda \,x \right ) \LegendreP \left ( 1/2\,{\frac {2\,a-\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) y-2\,\LegendreP \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) \lambda \,\cos \left ( 2\,\lambda \,x \right ) +2\,\LegendreP \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) \lambda \right ) \left ( \cos \left ( 3\,\lambda \,x \right ) \LegendreQ \left ( 1/2\,{\frac {2\,a-\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) a+3\,\sin \left ( \lambda \,x \right ) \LegendreQ \left ( 1/2\,{\frac {2\,a-\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) y-\cos \left ( \lambda \,x \right ) \LegendreQ \left ( 1/2\,{\frac {2\,a-\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) a-\sin \left ( 3\,\lambda \,x \right ) \LegendreQ \left ( 1/2\,{\frac {2\,a-\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) y-2\,\LegendreQ \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) \cos \left ( 2\,\lambda \,x \right ) \lambda +2\,\LegendreQ \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) \lambda \right ) ^{-1}} \right ) \]

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55.5 problem number 5

problem number 493

Added January 20, 2019.

Problem 2.6.4.5 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\)

\[ w_x + \left ( y^2+\lambda ^2 + 3 a \lambda +a(\lambda -a) \cot ^2(\lambda x) \right ) w_y = 0 \]

Mathematica

ClearAll[w, x, y, n, a, b, m, c, k, alpha, beta, gamma, A, C0, s, lambda, B, s, mu, d, g, B]; 
 pde = D[w[x, y], x] + (y^2 + lambda^2 + 3*a*lambda + a*(lambda - a)*Cot[lambda*x]^2)*D[w[x, y], y] == 0; 
 sol = AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

\[ \text {Failed} \]

Maple

 
w:='w';x:='x';y:='y';a:='a';b:='b';n:='n';m:='m';c:='c';k:='k';alpha:='alpha';beta:='beta';g:='g';A:='A'; C:='C';lambda:='lambda';B:='B';mu:='mu';d:='d';s:='s'; 
pde :=   diff(w(x,y),x)+ (  y^2+lambda^2 + 3*a*lambda +a*(lambda-a)*cot(lambda*x)^2   )*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[ w \left ( x,y \right ) ={\it \_F1} \left ( -{1 \left ( 2\,\cos \left ( \lambda \,x \right ) \left ( \sin \left ( \lambda \,x \right ) \right ) ^{2}\LegendreP \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) a+3\,\cos \left ( \lambda \,x \right ) \left ( \sin \left ( \lambda \,x \right ) \right ) ^{2}\LegendreP \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) \lambda +2\,\sin \left ( \lambda \,x \right ) \left ( \cos \left ( \lambda \,x \right ) \right ) ^{2}\LegendreP \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) y+ \left ( \cos \left ( \lambda \,x \right ) \right ) ^{3}\LegendreP \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) \lambda -4\, \left ( \sin \left ( \lambda \,x \right ) \right ) ^{2}\LegendreP \left ( 1/2\,{\frac {2\,a+3\,\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) \lambda -2\,\sin \left ( \lambda \,x \right ) \LegendreP \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) y-\LegendreP \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) \lambda \,\cos \left ( \lambda \,x \right ) \right ) \left ( 2\, \left ( \sin \left ( \lambda \,x \right ) \right ) ^{2}\cos \left ( \lambda \,x \right ) \LegendreQ \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) a+3\, \left ( \sin \left ( \lambda \,x \right ) \right ) ^{2}\cos \left ( \lambda \,x \right ) \LegendreQ \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) \lambda +2\,\sin \left ( \lambda \,x \right ) \left ( \cos \left ( \lambda \,x \right ) \right ) ^{2}\LegendreQ \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) y+ \left ( \cos \left ( \lambda \,x \right ) \right ) ^{3}\LegendreQ \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) \lambda -4\, \left ( \sin \left ( \lambda \,x \right ) \right ) ^{2}\LegendreQ \left ( 1/2\,{\frac {2\,a+3\,\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) \lambda -2\,\sin \left ( \lambda \,x \right ) \LegendreQ \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) y-\cos \left ( \lambda \,x \right ) \LegendreQ \left ( 1/2\,{\frac {2\,a+\lambda }{\lambda }},1/2\,{\frac {2\,a-\lambda }{\lambda }},\cos \left ( \lambda \,x \right ) \right ) \lambda \right ) ^{-1}} \right ) \]

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55.6 problem number 6

problem number 494

Added January 20, 2019.

Problem 2.6.4.6 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\)

\[ w_x + \left ( y^2-2 a \cot (a x) y + b^2-a^2 \right ) w_y = 0 \]

Mathematica

ClearAll[w, x, y, n, a, b, m, c, k, alpha, beta, gamma, A, C0, s, lambda, B, s, mu, d, g, B]; 
 pde = D[w[x, y], x] + (y^2 - 2*a*Cot[a*x]*y + b^2 - a^2)*D[w[x, y], y] == 0; 
 sol = AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

\[ \left \{\left \{w(x,y)\to c_1\left (\tan ^{-1}\left (\frac {\sqrt {b^2} y-a \sqrt {b^2} \cot (a x)}{b^2}\right )-\sqrt {b^2} x\right )\right \}\right \} \]

Maple

 
w:='w';x:='x';y:='y';a:='a';b:='b';n:='n';m:='m';c:='c';k:='k';alpha:='alpha';beta:='beta';g:='g';A:='A'; C:='C';lambda:='lambda';B:='B';mu:='mu';d:='d';s:='s'; 
pde :=   diff(w(x,y),x)+ (  y^2-2*a*cot(a*x)*y + b^2-a^2)*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[ w \left ( x,y \right ) ={\it \_F1} \left ( 1/2\,{\frac {{{\rm e}^{-2\,ibx}} \left ( -i\cot \left ( ax \right ) a+iy+b \right ) }{b \left ( ib-a\cot \left ( ax \right ) +y \right ) }} \right ) \]

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55.7 problem number 7

problem number 495

Added January 20, 2019.

Problem 2.6.4.7 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\)

\[ \cot (\lambda x) w_x + a \cot (\mu y) w_y = 0 \]

Mathematica

ClearAll[w, x, y, n, a, b, m, c, k, alpha, beta, gamma, A, C0, s, lambda, B, s, mu, d, g, B]; 
 pde = Cot[lambda*x]*D[w[x, y], x] + a*Cot[mu*y]*D[w[x, y], y] == 0; 
 sol = AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

\[ \left \{\left \{w(x,y)\to c_1\left (\frac {2 \cos (\mu y) \cos ^{-\frac {a \mu }{\lambda }}(\lambda x)}{\mu }\right )\right \}\right \} \]

Maple

 
w:='w';x:='x';y:='y';a:='a';b:='b';n:='n';m:='m';c:='c';k:='k';alpha:='alpha';beta:='beta';g:='g';A:='A'; C:='C';lambda:='lambda';B:='B';mu:='mu';d:='d';s:='s'; 
pde :=   cot(lambda*x)*diff(w(x,y),x)+ a*cot(mu*y)*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[ w \left ( x,y \right ) ={\it \_F1} \left ( 1/2\,{\frac {1}{\lambda \,\mu } \left ( \ln \left ( {\frac { \left ( \cot \left ( \lambda \,x \right ) \right ) ^{2}+1}{ \left ( \cot \left ( \lambda \,x \right ) \right ) ^{2}}} \right ) \mu \,a+\lambda \,\ln \left ( \left ( \cos \left ( \mu \,y \right ) \right ) ^{2} \right ) \right ) } \right ) \]

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55.8 problem number 8

problem number 496

Added January 20, 2019.

Problem 2.6.4.8 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\)

\[ \cot (\mu y) w_x + a \cot (\lambda x) w_y = 0 \]

Mathematica

ClearAll[w, x, y, n, a, b, m, c, k, alpha, beta, gamma, A, C0, s, lambda, B, s, mu, d, g, B]; 
 pde = Cot[mu*y]*D[w[x, y], x] + a*Cot[lambda*x]*D[w[x, y], y] == 0; 
 sol = AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

\[ \left \{\left \{w(x,y)\to c_1\left (\frac {2 \sin (\mu y) \sin ^{-\frac {a \mu }{\lambda }}(\lambda x)}{\mu }\right )\right \}\right \} \]

Maple

 
w:='w';x:='x';y:='y';a:='a';b:='b';n:='n';m:='m';c:='c';k:='k';alpha:='alpha';beta:='beta';g:='g';A:='A'; C:='C';lambda:='lambda';B:='B';mu:='mu';d:='d';s:='s'; 
pde :=   cot(mu*y)*diff(w(x,y),x)+ a*cot(lambda*x)*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[ w \left ( x,y \right ) ={\it \_F1} \left ( {\frac {1}{\mu \,a}\ln \left ( {\frac {\tan \left ( \mu \,y \right ) }{ \left ( \tan \left ( \mu \,y \right ) \right ) ^{2}+1}\sqrt { \left ( \left ( \tan \left ( \mu \,y \right ) \right ) ^{2}+1 \right ) \left ( -2\, \left ( -1+\cos \left ( 2\,\lambda \,x \right ) \right ) ^{-1} \right ) ^{{\frac {\mu \,a}{\lambda }}}}} \right ) } \right ) \]

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55.9 problem number 9

problem number 497

Added January 20, 2019.

Problem 2.6.4.9 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\)

\[ \cot (\mu y) w_x + a \cot ^2(\lambda x) w_y = 0 \]

Mathematica

ClearAll[w, x, y, n, a, b, m, c, k, alpha, beta, gamma, A, C0, s, lambda, B, s, mu, d, g, B]; 
 pde = Cot[mu*y]*D[w[x, y], x] + a*Cot[lambda*x]^2*D[w[x, y], y] == 0; 
 sol = AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

\[ \left \{\left \{w(x,y)\to c_1\left (\frac {4 \sin (\mu y) e^{\frac {a \mu (\lambda x+\cot (\lambda x))}{\lambda }}}{\mu }\right )\right \}\right \} \]

Maple

 
w:='w';x:='x';y:='y';a:='a';b:='b';n:='n';m:='m';c:='c';k:='k';alpha:='alpha';beta:='beta';g:='g';A:='A'; C:='C';lambda:='lambda';B:='B';mu:='mu';d:='d';s:='s'; 
pde :=   cot(mu*y)*diff(w(x,y),x)+ a*cot(lambda*x)^2*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[ w \left ( x,y \right ) ={\it \_F1} \left ( -1/2\,{\frac {1}{\lambda \,\sin \left ( \lambda \,x \right ) \mu \,a} \left ( \pi \,\sin \left ( \lambda \,x \right ) \mu \,a-2\,{\rm arccot} \left ({\frac {\cos \left ( \lambda \,x \right ) }{\sin \left ( \lambda \,x \right ) }}\right )\sin \left ( \lambda \,x \right ) \mu \,a-\ln \left ( {\frac { \left ( \tan \left ( \mu \,y \right ) \right ) ^{2}}{ \left ( \tan \left ( \mu \,y \right ) \right ) ^{2}+1}} \right ) \lambda \,\sin \left ( \lambda \,x \right ) -2\,\cos \left ( \lambda \,x \right ) \mu \,a \right ) } \right ) \]

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55.10 problem number 10

problem number 498

Added January 20, 2019.

Problem 2.6.4.10 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\)

\[ \cot (y+a) w_x + c \cot (x+b) w_y = 0 \]

Mathematica

ClearAll[w, x, y, n, a, b, m, c, k, alpha, beta, gamma, A, C0, s, lambda, B, s, mu, d, g, B]; 
 pde = Cot[y + a]*D[w[x, y], x] + c*Cot[x + b]^2*D[w[x, y], y] == 0; 
 sol = AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

\[ \left \{\left \{w(x,y)\to c_1\left (4 \sin (a+y) e^{c (\cot (b+x)+x)}\right )\right \}\right \} \]

Maple

 
w:='w';x:='x';y:='y';a:='a';b:='b';n:='n';m:='m';c:='c';k:='k';alpha:='alpha';beta:='beta';g:='g';A:='A'; C:='C';lambda:='lambda';B:='B';mu:='mu';d:='d';s:='s'; 
pde :=   cot(y+a)*diff(w(x,y),x)+ c*cot(x+b)^2*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[ w \left ( x,y \right ) ={\it \_F1} \left ( 1/2\,{\frac {1}{\tan \left ( b \right ) \left ( \tan \left ( x \right ) +\tan \left ( b \right ) \right ) } \left ( \pi \, \left ( \tan \left ( b \right ) \right ) ^{2}c+\pi \,\tan \left ( b \right ) \tan \left ( x \right ) c-2\, \left ( \tan \left ( b \right ) \right ) ^{2}cx-2\,\tan \left ( b \right ) \tan \left ( x \right ) cx+2\, \left ( \tan \left ( b \right ) \right ) ^{2}\tan \left ( x \right ) c+\ln \left ( \left ( \sin \left ( y \right ) \right ) ^{-2} \right ) \left ( \tan \left ( b \right ) \right ) ^{2}+\ln \left ( \left ( \sin \left ( y \right ) \right ) ^{-2} \right ) \tan \left ( b \right ) \tan \left ( x \right ) -2\,\ln \left ( {\frac {\cos \left ( y \right ) \tan \left ( a \right ) +\sin \left ( y \right ) }{\sin \left ( y \right ) \tan \left ( a \right ) }} \right ) \left ( \tan \left ( b \right ) \right ) ^{2}-2\,\ln \left ( {\frac {\cos \left ( y \right ) \tan \left ( a \right ) +\sin \left ( y \right ) }{\sin \left ( y \right ) \tan \left ( a \right ) }} \right ) \tan \left ( b \right ) \tan \left ( x \right ) +2\,c\tan \left ( x \right ) \right ) } \right ) \]

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55.11 problem number 11

problem number 499

Added January 20, 2019.

Problem 2.6.4.11 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\)

\[ \cot (\lambda x) \cot (\mu y) w_x + a w_y = 0 \]

Mathematica

ClearAll[w, x, y, n, a, b, m, c, k, alpha, beta, gamma, A, C0, s, lambda, B, s, mu, d, g, B]; 
 pde = Cot[lambda*x]*Cot[mu*y]*D[w[x, y], x] + a*D[w[x, y], y] == 0; 
 sol = AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

\[ \left \{\left \{w(x,y)\to c_1\left (\frac {2 \sin (\mu y) \cos ^{\frac {a \mu }{\lambda }}(\lambda x)}{\mu }\right )\right \}\right \} \]

Maple

 
w:='w';x:='x';y:='y';a:='a';b:='b';n:='n';m:='m';c:='c';k:='k';alpha:='alpha';beta:='beta';g:='g';A:='A'; C:='C';lambda:='lambda';B:='B';mu:='mu';d:='d';s:='s'; 
pde :=   cot(lambda*x)*cot(mu*y)*diff(w(x,y),x)+ a*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[ w \left ( x,y \right ) ={\it \_F1} \left ( {\frac {1}{\mu \,a}\ln \left ( {\frac {\tan \left ( \mu \,y \right ) }{ \left ( \tan \left ( \mu \,y \right ) \right ) ^{2}+1}\sqrt { \left ( \left ( \tan \left ( \mu \,y \right ) \right ) ^{2}+1 \right ) \left ( \cos \left ( \lambda \,x \right ) \right ) ^{2\,{\frac {\mu \,a}{\lambda }}}}} \right ) } \right ) \]

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55.12 problem number 12

problem number 500

Added January 20, 2019.

Problem 2.6.4.12 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\)

\[ \cot (\lambda x) \cot (\mu y) w_x + a \cot (v x) w_y = 0 \]

Mathematica

ClearAll[w, x, y, n, a, b, m, c, k, alpha, beta, gamma, A, C0, s, lambda, B, s, mu, d, g, B, v]; 
 pde = Cot[lambda*x]*Cot[mu*y]*D[w[x, y], x] + a*Cot[v*x]*D[w[x, y], y] == 0; 
 sol = AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

\[ \text {\$Aborted} \]

Maple

 
w:='w';x:='x';y:='y';a:='a';b:='b';n:='n';m:='m';c:='c';k:='k';alpha:='alpha';beta:='beta';g:='g';A:='A'; 
C:='C';lambda:='lambda';B:='B';mu:='mu';d:='d';s:='s';v:='v'; 
pde :=   cot(lambda*x)*cot(mu*y)*diff(w(x,y),x)+ a*cot(v*x)*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[ w \left ( x,y \right ) ={\it \_F1} \left ( {\frac {1}{\mu \,a}\ln \left ( {{\it csgn} \left ( \left ( \cos \left ( \mu \,y \right ) \right ) ^{-1} \right ) \sin \left ( \mu \,y \right ) {{\rm e}^{x\mu \,a}} \left ( {{\rm e}^{2\,ivx}}-1 \right ) ^{{\frac {i\mu \,a}{v}}} \left ( {{\rm e}^{\mu \,a\int \!-2\,{\frac {{{\rm e}^{2\,ivx}}+1}{ \left ( {{\rm e}^{2\,ivx}}-1 \right ) \left ( {{\rm e}^{2\,i\lambda \,x}}+1 \right ) }}\,{\rm d}x}} \right ) ^{-1}} \right ) } \right ) \]