t=var('t')
Y=function('Y',t)
DE = 2*diff(diff(Y,t),t) + 20000*Y 
d(t)=desolve (DE,[Y,t])
d1(t)=diff(d(t),t)
k1,k2=var('k1,k2')
solve([d(0)==0,
       d1(0)==55],k1,k2)
d=d1(t).subs(k1 =(11/20), k2 =0)
print d

SageDays/Kreyszig-2.12-14 (last edited 2010-08-12 08:41:03 by hardikgajera)