7.2.9 4.2

7.2.9.1 [589] problem number 1

problem number 589

Added January 10, 2019.

Problem 2.4.2.1 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\) \[ w_x + a \left ( \cosh (\lambda x)\right )w_y = 0 \]

Mathematica ✓

ClearAll["Global`*"]; 
pde =  D[w[x, y], x] + a*Cosh[lambda*x]*D[w[x, y], y] == 0; 
sol =  AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

\[\left \{\left \{w(x,y)\to c_1\left (y-\frac {a \sinh (\lambda x)}{\lambda }\right )\right \}\right \}\]

Maple ✓

restart; 
pde := diff(w(x,y),x)+ a*cosh(lambda*x)*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[w \left (x , y\right ) = \textit {\_F1} \left (\frac {-a \sinh \left (\lambda x \right )+\lambda y}{\lambda }\right )\]

____________________________________________________________________________________

7.2.9.2 [590] problem number 2

problem number 590

Added January 10, 2019.

Problem 2.4.2.2 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\) \[ w_x + a \left ( \cosh (\lambda x)\right )w_y = 0 \]

Mathematica ✓

ClearAll["Global`*"]; 
pde =  D[w[x, y], x] + a*Cosh[lambda*y]*D[w[x, y], y] == 0; 
sol =  AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

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

Maple ✓

restart; 
pde := diff(w(x,y),x)+ a*cosh(lambda*y)*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[w \left (x , y\right ) = \textit {\_F1} \left (\frac {-a \lambda x +2 \arctan \left ({\mathrm e}^{\lambda y}\right )}{a \lambda }\right )\]

____________________________________________________________________________________

7.2.9.3 [591] problem number 3

problem number 591

Added January 10, 2019.

Problem 2.4.2.3 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\) \[ w_x + \left ( (a \cosh ^2(\lambda x)-\lambda ) y^2 - a \cosh ^2(\lambda x)+ \lambda + a \right )w_y = 0 \]

Mathematica ✗

ClearAll["Global`*"]; 
pde =  D[w[x, y], x] + ((a*Cosh[lambda*x]^2 - lambda)*y^2 - a*Cosh[lambda*x]^2 + lambda + a)*D[w[x, y], y] == 0; 
sol =  AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

Failed

Maple ✓

restart; 
pde := diff(w(x,y),x)+ ( (a *cosh(lambda*x)^2-lambda)*y^2 - a*cosh(lambda*x)^2+ lambda + a)*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[w \left (x , y\right ) = \textit {\_F1} \left (-\frac {8 \left (\left (a \left (\cosh ^{2}\left (\lambda x \right )\right )-\lambda \right ) y \left (\cosh ^{4}\left (\lambda x \right )\right )-\frac {\left (\cosh \left (2 \lambda x \right )+1\right ) \left (a \cosh \left (2 \lambda x \right )+a -2 \lambda \right ) \sinh \left (2 \lambda x \right )}{8}\right ) \sqrt {\cosh \left (2 \lambda x \right )-1}}{4 \sqrt {\cosh \left (2 \lambda x \right )+1}\, \left (a \cosh \left (2 \lambda x \right )+a -2 \lambda \right ) \lambda \,{\mathrm e}^{\frac {a \cosh \left (2 \lambda x \right )}{2 \lambda }} \sinh \left (2 \lambda x \right )+8 \left (\left (a \left (\cosh ^{2}\left (\lambda x \right )\right )-\lambda \right ) y \left (\cosh ^{4}\left (\lambda x \right )\right )-\frac {\left (\cosh \left (2 \lambda x \right )+1\right ) \left (a \cosh \left (2 \lambda x \right )+a -2 \lambda \right ) \sinh \left (2 \lambda x \right )}{8}\right ) \sqrt {\cosh \left (2 \lambda x \right )-1}\, \left (\int \frac {2 \left (a \cosh \left (2 \lambda x \right )+a -2 \lambda \right ) \lambda \,{\mathrm e}^{\frac {a \cosh \left (2 \lambda x \right )}{2 \lambda }} \sinh \left (2 \lambda x \right )}{\sqrt {\cosh \left (2 \lambda x \right )-1}\, \left (\cosh \left (2 \lambda x \right )+1\right )^{\frac {3}{2}}}d x \right )}\right )\]

____________________________________________________________________________________

7.2.9.4 [592] problem number 4

problem number 592

Added January 10, 2019.

Problem 2.4.2.4 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\) \[ 2 w_x + \left ( (a - \lambda + a \cosh (\lambda x)) y^2 + a+ \lambda - a \cosh (\lambda x)\right )w_y = 0 \]

Mathematica ✗

ClearAll["Global`*"]; 
pde =  2*D[w[x, y], x] + ((a - lambda + a*Cosh[lambda*x])*y^2 + a + lambda - a*Cosh[lambda*x])*D[w[x, y], y] == 0; 
sol =  AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

Failed

Maple ✓

restart; 
pde := 2*diff(w(x,y),x)+ ( (a - lambda + a*cosh(lambda*x))*y^2 + a+ lambda- a *cosh(lambda*x))*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[w \left (x , y\right ) = \textit {\_F1} \left (\frac {\left (\cosh \left (\lambda x \right )+1\right )^{\frac {3}{2}} \sqrt {\cosh \left (\lambda x \right )-1}\, \left (y \cosh \left (\lambda x \right )+y -\sinh \left (\lambda x \right )\right )}{-2 \left (\cosh \left (\lambda x \right )+1\right ) \lambda \,{\mathrm e}^{\frac {a \cosh \left (\lambda x \right )}{\lambda }} \sinh \left (\lambda x \right )+\sqrt {\cosh \left (\lambda x \right )-1}\, \left (-\left (\cosh \left (\lambda x \right )+1\right )^{\frac {5}{2}} y +\left (\cosh \left (\lambda x \right )+1\right )^{\frac {3}{2}} \sinh \left (\lambda x \right )\right ) \left (\int \frac {\left (a \cosh \left (\lambda x \right )+a -\lambda \right ) \lambda \,{\mathrm e}^{\frac {a \cosh \left (\lambda x \right )}{\lambda }} \sinh \left (\lambda x \right )}{\left (\cosh \left (\lambda x \right )+1\right )^{\frac {3}{2}} \sqrt {\cosh \left (\lambda x \right )-1}}d x \right )}\right )\]

____________________________________________________________________________________

7.2.9.5 [593] problem number 5

problem number 593

Added January 10, 2019.

Problem 2.4.2.5 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\) \[ \left (a x^n+ b x \cosh ^m(y) \right ) w_x + y^k w_y = 0 \]

Mathematica ✗

ClearAll["Global`*"]; 
pde =  (a*x^n + b*x*Cosh[y]^m)*D[w[x, y], x] + y^k*D[w[x, y], y] == 0; 
sol =  AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

Failed

Maple ✓

restart; 
pde := (a*x^n+ b*x*cosh(y)^m)*diff(w(x,y),x)+ y^k*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[w \left (x , y\right ) = \textit {\_F1} \left (\left (n -1\right ) a \left (\int y^{-k} {\mathrm e}^{\left (n -1\right ) b \left (\int y^{-k} \left (\cosh ^{m}\left (y \right )\right )d y \right )}d y \right )+x^{-n +1} {\mathrm e}^{\left (n -1\right ) b \left (\int y^{-k} \left (\cosh ^{m}\left (y \right )\right )d y \right )}\right )\]

____________________________________________________________________________________

7.2.9.6 [594] problem number 6

problem number 594

Added January 10, 2019.

Problem 2.4.2.6 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\) \[ \left (a x^n+ b x \cosh ^m(y) \right ) w_x + \cosh ^k(\lambda y) w_y = 0 \]

Mathematica ✗

ClearAll["Global`*"]; 
pde =  (a*x^n + b*x*Cosh[y]^m)*D[w[x, y], x] + Cosh[lambda*y]^k*D[w[x, y], y] == 0; 
sol =  AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

Failed

Maple ✓

restart; 
pde := (a*x^n+ b*x*cosh(y)^m)*diff(w(x,y),x)+cosh(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'));
 

\[w \left (x , y\right ) = \textit {\_F1} \left (\left (n -1\right ) a \left (\int \left (\cosh ^{-k}\left (\lambda y \right )\right ) {\mathrm e}^{\left (n -1\right ) b \left (\int \left (\cosh ^{m}\left (y \right )\right ) \left (\cosh ^{-k}\left (\lambda y \right )\right )d y \right )}d y \right )+x^{-n +1} {\mathrm e}^{\left (n -1\right ) b \left (\int \left (\cosh ^{m}\left (y \right )\right ) \left (\cosh ^{-k}\left (\lambda y \right )\right )d y \right )}\right )\]

____________________________________________________________________________________

7.2.9.7 [595] problem number 7

problem number 595

Added January 10, 2019.

Problem 2.4.2.7 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\) \[ \left (a x^n y^m+ b x \right ) w_x + \cosh ^k(\lambda y) w_y = 0 \]

Mathematica ✗

ClearAll["Global`*"]; 
pde =  (a*x^n*y^m + b*x)*D[w[x, y], x] + Cosh[lambda*y]^k*D[w[x, y], y] == 0; 
sol =  AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

Failed

Maple ✓

restart; 
pde := (a*x^n*y^m+ b*x)*diff(w(x,y),x)+cosh(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'));
 

\[w \left (x , y\right ) = \textit {\_F1} \left (\left (n -1\right ) a \left (\int y^{m} \left (\cosh ^{-k}\left (\lambda y \right )\right ) {\mathrm e}^{\left (n -1\right ) b \left (\int \left (\cosh ^{-k}\left (\lambda y \right )\right )d y \right )}d y \right )+x^{-n +1} {\mathrm e}^{\left (n -1\right ) b \left (\int \left (\cosh ^{-k}\left (\lambda y \right )\right )d y \right )}\right )\]

____________________________________________________________________________________

7.2.9.8 [596] problem number 8

problem number 596

Added January 10, 2019.

Problem 2.4.2.8 from Handbook of first order partial differential equations by Polyanin, Zaitsev, Moussiaux.

Solve for \(w(x,y)\) \[ \left (\cosh (\mu y) \right ) w_x + a \cosh (\lambda x) w_y = 0 \]

Mathematica ✓

ClearAll["Global`*"]; 
pde =  Cosh[mu*y]*D[w[x, y], x] + a*Cosh[lambda*x]*D[w[x, y], y] == 0; 
sol =  AbsoluteTiming[TimeConstrained[DSolve[pde, w[x, y], {x, y}], 60*10]];
 

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

Maple ✓

restart; 
pde := cosh(mu*y)*diff(w(x,y),x)+a*cosh(lambda*x)*diff(w(x,y),y) = 0; 
cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,w(x,y))),output='realtime'));
 

\[w \left (x , y\right ) = \textit {\_F1} \left (\frac {-a \mu \sinh \left (\lambda x \right )+\lambda \sinh \left (\mu y \right )}{a \lambda \mu }\right )\]

____________________________________________________________________________________