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Error attempting to use initial conditions


I'm doing a quick problem in Maple with a differential equation and a few initial conditions, but I'm getting an error message that I can't seem to understand given the context. Can anyone quickly elaborate on what's going on here? How do I fix this issue?

> KVLl2 := -4*(i2(t)-2)-12*(i2(t)-i3(t)) = 0;
              -16 i2(t) + 8 + 12 i3(t) = 0
> KVLl3 := -12*(i3(t)-i2(t))-4*i3(t)-3.5*(diff(i3(t), t)) = 0;
                                  / d       \    
       -16 i3(t) + 12 i2(t) - 3.5 |--- i3(t)| = 0
                                  \ dt      /    
> mySoln := dsolve({KVLl2, KVLl3, i2(0) = 1, i3(0) = 1}, i2, i3);

Error, (in dsolve) found the following equations not depending 
on the unknowns of the input system: {1 = 1}

Thanks in advance


Solution

  • Maple doesn't know what to do with i2 and i3 you provided as target functions. If you look at the help of dsolve (?dsolve), you see that it requires its target functions to be specified in terms of their variables (t in this case) and as a list. Try using this

    dsolve({KVLl2, KVLl3, i2(0) = 1, i3(0) = 1}, {i2(t), i3(t)});
    

    No errors here but no solution either (this might be related to your equation)