119
119
/* Non-constant invariant */
120
120
(kn_(36),ans:ode1_abel(eqn:'diff(y,x)+y^3+a*x*y^2,y,x));
123
123
(kn_(37),ans:ode1_abel(eqn:'diff(y,x)-y^3-a*exp(x)*y^2,y,x));
126
126
(kn_(40),ans:ode1_abel(eqn:'diff(y,x)+3*a*y^3+6*a*x*y^2,y,x));
129
129
(kn_(42),ans:ode1_abel(eqn:'diff(y,x)-x*(x+2)*y^3-(x+3)*y^2,y,x));
132
132
(kn_(43),ans:ode1_abel(eqn:'diff(y,x)+(3*a*x^2+4*a^2*x+b)*y^3+3*x*y^2,y,x));
135
135
(kn_(45),ans:ode1_abel(eqn:'diff(y,x)+2*(a^2*x^3-b^2*x)*y^3+3*b*y^2,y,x));
138
138
/* Abel equations of second kind */
139
(kn_(213),ans:ode1_abel(eqn:(y+1)*'DIFF(y,x)=y+x,y,x));
140
[-(LOG((2*(x-1)/(y+1)-SQRT(5)+1)/(2*(x-1)/(y+1)+SQRT(5)+1))+SQRT(5)*LOG((x-1)/(y+1)+(x-1)^2/(y+1)^2-1)-2*SQRT(5)*LOG((x-1)/(y+1)))/(2*SQRT(5))=LOG(x-1)+%C];
141
[method,ode_check(eqn,ans[1])];
144
(kn_(214),ans:ode1_abel(eqn:(y+x-1)*'DIFF(y,x)-y+2*x+3=0,y,x));
145
[-(2*ATAN((1-(3*x+2)/(y+x-1))/SQRT(2))+SQRT(2)*LOG(-2*(3*x+2)/(y+x-1)+(3*x+2)^2/(y+x-1)^2+3)-2*SQRT(2)*LOG(-(3*x+2)/(2*(y+x-1))))/(6*SQRT(2))=LOG(3*x+2)/3+%C];
146
[method,ode_check(eqn,ans[1])];
149
(kn_(215),ans:ode1_abel(eqn:(y+2*x-2)*'DIFF(y,x)-y+x+1=0,y,x));
150
[-(6*ATAN((3-2*(3*x-1)/(y+2*x-2))/SQRT(3))+SQRT(3)*LOG(-(3*x-1)/(y+2*x-2)+(3*x-1)^2/(3*(y+2*x-2)^2)+1)-2*SQRT(3)*LOG(-(3*x-1)/(3*(y+2*x-2))))/(6*SQRT(3))=LOG(3*x-1)/3+%C];
151
[method,ode_check(eqn,ans[1])];
154
(kn_(216),ans:ode1_abel(eqn:(y-2*x+1)*'DIFF(y,x)+y+x=0,y,x));
155
[-(6*ATAN((2*(3*x-1)/(y-2*x+1)+3)/SQRT(3))+SQRT(3)*LOG((3*x-1)/(y-2*x+1)+(3*x-1)^2/(3*(y-2*x+1)^2)+1)-2*SQRT(3)*LOG((3*x-1)/(3*(y-2*x+1))))/(6*SQRT(3))=LOG(3*x-1)/3+%C];
156
[method,ode_check(eqn,ans[1])];
159
(kn_(217),ans:ode1_abel(eqn:(y-x^2)*'DIFF(y,x)=x,y,x));
139
(kn_(213),ans:ode1_abel(eqn:(y+1)*'diff(y,x)=y+x,y,x));
140
[-(log((2*(x-1)/(y+1)-sqrt(5)+1)/(2*(x-1)/(y+1)+sqrt(5)+1))+sqrt(5)*log((x-1)/(y+1)+(x-1)^2/(y+1)^2-1)-2*sqrt(5)*log((x-1)/(y+1)))/(2*sqrt(5))=log(x-1)+%c];
141
[method,ode_check(eqn,ans[1])];
144
(kn_(214),ans:ode1_abel(eqn:(y+x-1)*'diff(y,x)-y+2*x+3=0,y,x));
145
[-(2*atan((1-(3*x+2)/(y+x-1))/sqrt(2))+sqrt(2)*log(-2*(3*x+2)/(y+x-1)+(3*x+2)^2/(y+x-1)^2+3)-2*sqrt(2)*log(-(3*x+2)/(2*(y+x-1))))/(6*sqrt(2))=log(3*x+2)/3+%c];
146
[method,ode_check(eqn,ans[1])];
149
(kn_(215),ans:ode1_abel(eqn:(y+2*x-2)*'diff(y,x)-y+x+1=0,y,x));
150
[-(6*atan((3-2*(3*x-1)/(y+2*x-2))/sqrt(3))+sqrt(3)*log(-(3*x-1)/(y+2*x-2)+(3*x-1)^2/(3*(y+2*x-2)^2)+1)-2*sqrt(3)*log(-(3*x-1)/(3*(y+2*x-2))))/(6*sqrt(3))=log(3*x-1)/3+%c];
151
[method,ode_check(eqn,ans[1])];
154
(kn_(216),ans:ode1_abel(eqn:(y-2*x+1)*'diff(y,x)+y+x=0,y,x));
155
[-(6*atan((2*(3*x-1)/(y-2*x+1)+3)/sqrt(3))+sqrt(3)*log((3*x-1)/(y-2*x+1)+(3*x-1)^2/(3*(y-2*x+1)^2)+1)-2*sqrt(3)*log((3*x-1)/(3*(y-2*x+1))))/(6*sqrt(3))=log(3*x-1)/3+%c];
156
[method,ode_check(eqn,ans[1])];
159
(kn_(217),ans:ode1_abel(eqn:(y-x^2)*'diff(y,x)=x,y,x));
160
160
[(y-x^2)*(log(-1/(2*(y-x^2)))/(2*(y-x^2))-log(1-1/(2*(y-x^2)))/(2*(y-x^2))-1)/2= x^2/2+%c];
161
161
[method,ode_check(eqn,ans[1])];
164
(kn_(218),ans:ode1_abel(eqn:(y-x^2)*'DIFF(y,x)+4*x*y=0,y,x));
164
(kn_(218),ans:ode1_abel(eqn:(y-x^2)*'diff(y,x)+4*x*y=0,y,x));
165
165
[(log(2*x^2/(y-x^2)+2)-2*log(2*x^2/(y-x^2)+1)+log(2*x^2/(3*(y-x^2))))/2=log(x)+%c];
166
166
[method,ode_check(eqn,ans[1])];
169
169
/* Why does this fail? */
170
/* (kn_(220),ans:ode1_abel(eqn:2*y*'DIFF(y,x)-x*y^2-x^3=0,y,x));
171
[%E^-(x^2/2)*(y^2+x^2+2) = %C];
170
/* (kn_(220),ans:ode1_abel(eqn:2*y*'diff(y,x)-x*y^2-x^3=0,y,x));
171
[%e^-(x^2/2)*(y^2+x^2+2) = %c];
172
172
[method,ode_check(eqn,ans[1])];
175
(kn_(221),ans:ode1_abel(eqn:(2*y+x+1)*'DIFF(y,x)-(2*y+x-1)=0,y,x));
176
[-(2*y+x+1)*(-4*(2*(x+1)+2*(1-x))*LOG(1-(2*(x+1)+2*(1-x))/(3*(2*y+x+1)))/(3*(2*y+x+1))+4*(2*(x+1)+2*(1-x))*LOG(-(2*(x+1)+2*(1-x))/(3*(2*y+x+1)))/(3*(2*y+x+1))-4)/(3*(2*(x+1)+2*(1-x)))=x+%C];
175
(kn_(221),ans:ode1_abel(eqn:(2*y+x+1)*'diff(y,x)-(2*y+x-1)=0,y,x));
176
[-(2*y+x+1)*(-4*(2*(x+1)+2*(1-x))*log(1-(2*(x+1)+2*(1-x))/(3*(2*y+x+1)))/(3*(2*y+x+1))+4*(2*(x+1)+2*(1-x))*log(-(2*(x+1)+2*(1-x))/(3*(2*y+x+1)))/(3*(2*y+x+1))-4)/(3*(2*(x+1)+2*(1-x)))=x+%c];
177
177
[method,ode_check(eqn,ans[1])];