### 105 HFOPDE, chapter 4.4.4

105.1 Problem 1
105.2 Problem 2
105.3 Problem 3
105.4 Problem 4
105.5 Problem 5

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#### 105.1 Problem 1

problem number 884

Added Feb. 23, 2019.

Problem Chapter 4.4.4.1, from Handbook of ﬁrst order partial diﬀerential equations by Polyanin, Zaitsev, Moussiaux.

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

$a w_x + b w_y = (c \coth (\lambda x) + k \coth (\mu y)) w$

Mathematica

$\left \{\left \{w(x,y)\to c_1\left (y-\frac{b x}{a}\right ) \sinh ^{\frac{c}{a \lambda }}(\lambda x) \sinh ^{\frac{k}{b \mu }}(\mu y)\right \}\right \}$

Maple

$w \left ( x,y \right ) ={\it \_F1} \left ({\frac{ay-bx}{a}} \right ) \left ({\rm coth} \left (\lambda \,x\right )-1 \right ) ^{-1/2\,{\frac{c}{\lambda \,a}}} \left ({\rm coth} \left (\lambda \,x\right )+1 \right ) ^{-1/2\,{\frac{c}{\lambda \,a}}} \left ({\rm coth} \left (\mu \,y\right )-1 \right ) ^{-1/2\,{\frac{k}{\mu \,b}}} \left ({\rm coth} \left (\mu \,y\right )+1 \right ) ^{-1/2\,{\frac{k}{\mu \,b}}}$

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#### 105.2 Problem 2

problem number 885

Added Feb. 23, 2019.

Problem Chapter 4.4.4.2, from Handbook of ﬁrst order partial diﬀerential equations by Polyanin, Zaitsev, Moussiaux.

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

$a w_x + b w_y = c \coth (\lambda x +\mu y) w$

Mathematica

$\left \{\left \{w(x,y)\to c_1\left (y-\frac{b x}{a}\right ) \sinh ^{\frac{c}{a \lambda +b \mu }}(\lambda x+\mu y)\right \}\right \}$

Maple

$w \left ( x,y \right ) ={\it \_F1} \left ({\frac{ay-bx}{a}} \right ) \left ({\rm coth} \left (\lambda \,x+\mu \,y\right )-1 \right ) ^{-{\frac{c}{2\,\lambda \,a+2\,\mu \,b}}} \left ({\rm coth} \left (\lambda \,x+\mu \,y\right )+1 \right ) ^{-{\frac{c}{2\,\lambda \,a+2\,\mu \,b}}}$

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#### 105.3 Problem 3

problem number 886

Added Feb. 23, 2019.

Problem Chapter 4.4.4.3, from Handbook of ﬁrst order partial diﬀerential equations by Polyanin, Zaitsev, Moussiaux.

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

$x w_x + y w_y = a x \coth (\lambda x +\mu y) w$

Mathematica

$\left \{\left \{w(x,y)\to c_1\left (\frac{y}{x}\right ) \sinh ^{\frac{a}{\lambda +\frac{\mu y}{x}}}\left (x \left (\lambda +\frac{\mu y}{x}\right )\right )\right \}\right \}$

Maple

$w \left ( x,y \right ) ={\it \_F1} \left ({\frac{y}{x}} \right ) \left ({\rm coth} \left (\lambda \,x+\mu \,y\right )-1 \right ) ^{-1/2\,{a \left ({\frac{\mu \,y}{x}}+\lambda \right ) ^{-1}}} \left ({\rm coth} \left (\lambda \,x+\mu \,y\right )+1 \right ) ^{-1/2\,{a \left ({\frac{\mu \,y}{x}}+\lambda \right ) ^{-1}}}$

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#### 105.4 Problem 4

problem number 887

Added Feb. 23, 2019.

Problem Chapter 4.4.4.4, from Handbook of ﬁrst order partial diﬀerential equations by Polyanin, Zaitsev, Moussiaux.

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

$a w_x + b \coth ^n(\lambda x) w_y = (c \coth ^m(\mu x)+s \coth ^k(\beta y)) w$

Mathematica

$\text{Timed out}$ Timed out

Maple

$w \left ( x,y \right ) ={\it \_F1} \left ( -\int \!{\frac{b \left ({\rm coth} \left (\lambda \,x\right ) \right ) ^{n}}{a}}\,{\rm d}x+y \right ){{\rm e}^{\int ^{x}\!{\frac{1}{a} \left ( c \left ({\rm coth} \left (\mu \,{\it \_b}\right ) \right ) ^{m}+s \left ({\rm coth} \left (\beta \,\int \!{\frac{b \left ({\rm coth} \left (\lambda \,{\it \_b}\right ) \right ) ^{n}}{a}}\,{\rm d}{\it \_b}+ \left ( -\int \!{\frac{b \left ({\rm coth} \left (\lambda \,x\right ) \right ) ^{n}}{a}}\,{\rm d}x+y \right ) \beta \right ) \right ) ^{k} \right ) }{d{\it \_b}}}}$

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#### 105.5 Problem 5

problem number 888

Added Feb. 23, 2019.

Problem Chapter 4.4.4.5, from Handbook of ﬁrst order partial diﬀerential equations by Polyanin, Zaitsev, Moussiaux.

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

$a w_x + b \coth ^n(\lambda y) w_y = (c \coth ^m(\mu x)+s \coth ^k(\beta y)) w$

Mathematica

$\text{Timed out}$ Timed out

Maple

$w \left ( x,y \right ) ={\it \_F1} \left ( -{\frac{a\int \! \left ({\rm coth} \left (\lambda \,y\right ) \right ) ^{-n}\,{\rm d}y}{b}}+x \right ){{\rm e}^{\int ^{y}\!{\frac{ \left ({\rm coth} \left (\lambda \,{\it \_b}\right ) \right ) ^{-n}}{b} \left ( c \left ( -{\rm coth} \left (-\mu \,\int \!{\frac{ \left ({\rm coth} \left (\lambda \,{\it \_b}\right ) \right ) ^{-n}a}{b}}\,{\rm d}{\it \_b}-\mu \, \left ( -{\frac{a\int \! \left ({\rm coth} \left (\lambda \,y\right ) \right ) ^{-n}\,{\rm d}y}{b}}+x \right ) \right ) \right ) ^{m}+s \left ({\rm coth} \left (\beta \,{\it \_b}\right ) \right ) ^{k} \right ) }{d{\it \_b}}}}$