p5_5.dir

来自「Programs for the book Advanced Engineeri」· DIR 代码 · 共 12 行

format compactp5_5y3 =
C1+C2*t+C3*t^2
yb=dsolve('D3y-D2y-12*Dy=0','t')yb =
C1+C2*exp(-3*t)+C3*exp(4*t)
yc=dsolve('D2y+4*y=0','t')yc =
C1*sin(2*t)+C2*cos(2*t)
yd=dsolve('D2y+2*Dy+y=2*cos(2*t)+3*t+2+3*exp(t)','t')yd =
-2/5*cos(2*t)*t-6/25*cos(2*t)-4/5*sin(2*t)*t
+8/25*sin(2*t)+13/5*t-4+3/4*exp(t)+4/5*t*cos(t)^2
+8/5*t*cos(t)*sin(t)
+C1*exp(-t)+C2*exp(-t)*t
diary off