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Question: subs issue.

Question:subs issue.

PhyTch.Paul 38 Maple
subs
April 10 2006
0
I am trying to use the subs command to take a general solution to a differential equation and apply some numerical values. I can't seem to get the system to recognize the values I am substituting for. Consider the following: m*diff(y(t),t,t)=-m*g+sigma*A*diff(y(t),t); (1) y(0)=h,D(y)(0)=0; (2) dsolve( {(1),(2)} ); (3) subs( {A=2,m=50},rhs((3)) ); Everything works fine. If, on the other hand I impose any kind of constraint on A or m in the original equation then the substitution fails (nothing happens). Clearly the system has tagged the value for A and m as something other than their original name. Since the system doesn't report this name change how can I make substitutions after a symbolic manipulation like this? (OK I get that the value is now named A~ and m~ but how do I use these names since typing them in as such generates a syntax error)
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