Revision history [back]

What's about this version:

var('u,x,t')
erfc(x) = 1-erf(x)
k=3/100
D=3/10
C=2
u(x,t) = C*1/2*(erfc((x-k*t)/sqrt(4*D*t))+exp(x*k/D)*erfc((x+k*t)/sqrt(4*D*t)))
assume(x>0)
ans=limit(u(x,t),t=0,dir='+')
print ans.simplify_full()