test1 := (3*f-f^2)*(Diff(g, x))+(-f+3*f^2-2)*(Diff(g, y))+(2-f^2)*(Diff(g, z));

test1r := solve(test1=0,f);

how to solve this in terms of Diff(g,x), Diff(g,y) etc.

after solve, it is like a bug, because result is Diff(1,x) etc where is g?

there is a triangle, one side is t, another side is sqrt(1-t^2), however this do not need sqrt

i use sin law, can not dsolved the following equation, it can onlyl be solved for right angled triangle

is it only in circle's triangle be solved? 

besides triangle, the goal of mine to use another shape 

ode := diff(u(t),t)-f(t)=0,diff(f(t),t)+t*f(t)=0,diff(f(t),t$2)+(t*sin(a)*sin(b))^2*f(t)=0;  

ode := diff(u(t),t)-f(t)=0,diff(f(t...

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restart;

read("D:/Poset2/posets2.4v.txt"):

with(posets):

L := chain(2) &* chain(2);

plot_poset(L);

lattice(L);

autgroup(L);

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restart;

ode := diff(u(t),t)-f(t)=0 ,diff(f(t),t)+(t+sqrt(t^2-t*n))*f(t)=0,diff(f(t),t$2)+(1-(t+sqrt(t^2-t*n))^2)*f(t)=0;

dsolve({ode},[f(t),u(t)]);

sol[2] := [[2, 1], [3, 4]];

for i from 1 to nops(sol[2]) do

sol[2][i] := [seq(op(k,sol[2][i]), k=nops(sol[2][i])..1, -1)];

T := T + table([seq(op(k,sol[2][i])=op(k-1,sol[2][i]), k=2..nops(sol[2][i])),op(1,sol[2][i])=op(nops(sol[2][i]),sol[2][i])]);

od;

final result should be

1 2 3 4

2 1 4 3