Aleksas

odeL is function for solving linear ode with constant coefficients in form L(y)=f. Tray: (%i2) eq:'diff(y,r,1) = (R_s * y)/(2 * r * (r-R_s))$ ode2(eq,y,r),radcan; (%o2) y=(%c*sqrt(r-R_s))/sqrt(r) best 2019-01-12, št, 19:42 Daniel Volinski danielvolinski@users.sourceforge.net rašė: This bug has not been addressed yet. Daniel [bugs:#3510] https://sourceforge.net/p/maxima/bugs/3510/ odeL wrong results* Status: open Group: None Created: Sun Dec 16, 2018 07:25 AM UTC by Daniel Volinski Last Updated: Sun...

Function odeL is only for solving linear differential equation Ly=f with constant coefficients. For solving equation y' = (2 x + 3y + 1)/(4x + 6 y + 1) use contrib_ode or change u=2x+3y. In this case odeL must return "false" or some warning. I'm thinking about updated version of package odes. Merry Christmas Aleksas D. 2018-12-18, an, 09:19 Daniel Volinski danielvolinski@users.sourceforge.net rašė: [bugs:#3511] https://sourceforge.net/p/maxima/bugs/3511/ another odeL wrong result* Status: open Group:...

(%i2) eq1:x^2+y^2=r^2$ eq2:(x-a)^2+(y-b)^2=p^2$ (%i3) sol:solve([eq1,eq1-eq2],[x,y]); (sol) [[x=-(bsqrt(-r^4+(2p^2+2b^2+2a^2)r^2-p^4+(2b^2+2a^2)p^2-b^4-2a^2b^2-a^4)-ar^2+ap^2-ab^2-a^3)/(2b^2+2a^2),y=(asqrt(-r^4+(2p^2+2b^2+2a^2)r^2-p^4+(2b^2+2a^2)p^2-b^4-2a^2b^2-a^4)+br^2-bp^2+b^3+a^2b)/(2b^2+2a^2)],[x=(bsqrt(-r^4+(2p^2+2b^2+2a^2)r^2-p^4+(2b^2+2a^2)p^2-b^4-2a^2b^2-a^4)+ar^2-ap^2+ab^2+a^3)/(2b^2+2a^2),y=-(asqrt(-r^4+(2p^2+2b^2+2a^2)r^2-p^4+(2b^2+2a^2)p^2-b^4-2a^2b^2-a^4)-br^2+bp^2-b^3-a^2b)/(2b^2+2a^2)]]...

How we got the wrong result. Some details. (%i3) assume(x>0); define(g(t),h(t)/t^2); define(f(x),integrate(g(t),t,0,x)); (%o1) [x>0] (%o2) g(t):=h(t)/t^2 (%o3) f(x):=integrate(h(t)/t^2,t,0,x); (%i4) T:taylor(f(x),x,0,3); (T) h(0)/x+(5(at('diff(h(x),x,1),x=0)))/6+((at('diff(h(x),x,2),x=0))x)/2+((at('diff(h(x),x,3),x=0))x^2)/4+(7(at('diff(h(x),x,4),x=0))*x^3)/72+... (%i7) h(t):=cos(t)-1; ev(T, nouns); expand(%); (%o5) h(t):=cos(t)-1 (%o6)/R/ (7x^3-36x)/72 (%o7) (7*x^3)/72-x/2 2017-06-30 16:59 GMT+03:00...

How we got the wrong result. Some details. (%i3) assume(x>0); define(g(t),h(t)/t^2); define(f(x),integrate(g(t),t,0,x)); (%o1) [x>0] (%o2) g(t):=h(t)/t^2 (%o3) f(x):=integrate(h(t)/t^2,t,0,x); (%i4) T:taylor(f(x),x,0,3); (T) h(0)/x+(5(at('diff(h(x),x,1),x=0)))/6+((at('diff(h(x),x,2),x=0))x)/2+((at('diff(h(x),x,3),x=0))x^2)/4+ (7(at('diff(h(x),x,4),x=0))*x^3)/72+... (%i7) h(t):=cos(t)-1; ev(T, nouns); expand(%); (%o5) h(t):=cos(t)-1 (%o6)/R/ (7x^3-36x)/72 (%o7) (7*x^3)/72-x/2

Functions odeL, odeL_ic solves differential equations Ly = f, where L is linear differential...

solve with list of vars

after assume(x>0,x<1) plots are the same: (%i1) theta:0.4335379$ w:300$ mo:-3$ mp:-17$...