MaplePartSoln.mws

>    f:=A*x*exp(3*x)+B*x*sin(2*x)+C*x*cos(2*x);

f := A*x*exp(3*x)+B*x*sin(2*x)+C*x*cos(2*x)

>    diff(f,x$4)-diff(f,x$3)-2*diff(f,x,x)-4*diff(f,x)-24*f;

8*B*sin(2*x)+65*A*exp(3*x)+40*C*sin(2*x)+8*C*cos(2*x)-40*B*cos(2*x)

>    solve({65*A=1,8*B+40*C=0,8*C-40*B=6},{A,B,C});

{C = 3/104, A = 1/65, B = -15/104}

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