answer different on MATLAB than the expected answer

1 次查看(过去 30 天)
i have used this code to solve ODE
syms y(x)
Q_22= (diff(y,x,3))- (diff(y,x,2))== 6;
disp('The solution is:')
The solution is:
ySol(x) = simplify(dsolve(Q_22))
ySol(x) = 
But the expected answer i needed to be is as following :
these are the steps of solving it :

采纳的回答

Paul
Paul 2021-11-16
Mathematically, the answers are the same because the Ci are abitrary constants (absent any othe conditions on the solution). So the mapping from the Matlab solution to your solution is:
C1 + C2 - 6 -> C1
C1 - 6 -> C2
C3 -> C3
Or did you realize this and you just want to manipulate the Matlab solution to be in the same form as yours?
  2 个评论
Paul
Paul 2021-11-16
If you know the answer you're going for, at least after seeing the form of ySol, you can manipulate manually
syms y(x)
Q_22= (diff(y,x,3))- (diff(y,x,2))== 6;
ySol(x) = simplify(dsolve(Q_22))
ySol(x) = 
syms C1 C2 C3 K1 K2 K3
ySol = subs(ySol,[C1+C2-6,C1-6,C3],[K1 K2 K3])
ySol(x) = 
ySol = subs(ySol,[K1 K2 K3],[C1 C2 C3])
ySol(x) = 
Automating this process would be more work, assuming it's even feasible.

请先登录,再进行评论。

更多回答(0 个)

类别

Help CenterFile Exchange 中查找有关 Number Theory 的更多信息

产品


版本

R2020b

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by