# Question:Solving a system of pdes

## Question:Solving a system of pdes

Maple

I am trying to solve these equations but I dont know how...

> sys := [diff(v(s, n), n)+diff(u(s, n), s)+diff(xi(s, n), s)+A*n*(diff(c(s), s)) = 0, A1*(diff(xi(s, n), n))+diff(v(s, n), s)-c(s)+A2*v(s, n)+A3*c(s) = 0, diff(u(s, n), s)+2*A2*u(s, n) = A2*(xi(s, n)+A*n*c(s))-A1*(diff(xi(s, n), s))-A2*n*c(s)];

print(`output redirected...`); # input placeholder

[/ d         \   / d         \   / d          \       / d      \

[|--- v(s, n)| + |--- u(s, n)| + |--- xi(s, n)| + A n |--- c(s)| = 0,

[\ dn        /   \ ds        /   \ ds         /       \ ds     /

/ d          \   / d         \                                    / d

A1 |--- xi(s, n)| + |--- v(s, n)| - c(s) + A2 v(s, n) + A3 c(s) = 0, |--- u(

\ dn         /   \ ds        /                                    \ ds

\                                                / d          \

s, n)| + 2 A2 u(s, n) = A2 (xi(s, n) + A n c(s)) - A1 |--- xi(s, n)|

/                                                \ ds         /

]

- A2 n c(s)]

]

> sys;

print(`output redirected...`); # input placeholder

[/ d         \   / d         \   / d          \       / d      \

[|--- v(s, n)| + |--- u(s, n)| + |--- xi(s, n)| + A n |--- c(s)| = 0,

[\ dn        /   \ ds        /   \ ds         /       \ ds     /

/ d          \   / d         \                                    / d

A1 |--- xi(s, n)| + |--- v(s, n)| - c(s) + A2 v(s, n) + A3 c(s) = 0, |--- u(

\ dn         /   \ ds        /                                    \ ds

\                                                / d          \

s, n)| + 2 A2 u(s, n) = A2 (xi(s, n) + A n c(s)) - A1 |--- xi(s, n)|

/                                                \ ds         /

]

- A2 n c(s)]

]

> bc := {v(s, -1) = 0, v(s, 1) = 0};

print(`output redirected...`); # input placeholder

{v(s, -1) = 0, v(s, 1) = 0}

> ans := pdsolve(sys, bc);

%;

Error, (in pdsolve/sys/info) required an indication of the dependent variables in the given system

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