matlab解微分方程组

[a,b]=dsolve('Dy=-2*2.825678*10^-7*x*Dx','22050000*sin(atan(Dy/Dx))/(7056000-7500*t)-1.624=-5.652*10^-7*Dx^2-6.652*10^-1442537.6*cos(atan(Dy/Dx))/(7056000-7500*t)','t')
无解，求大神给求

>> s=dsolve('Dy=-2*2.825678*10^-7*x*Dx','22050000*sin(atan(Dy/Dx))/(7056000-7500*t)-1.624=-5.652*10^-7*Dx^2-6.652*10^-1442537.6*cos(atan(Dy/Dx))/(7056000-7500*t)','t')
Warning: Explicit solution could not be found.
> In dsolve at 197

s =

[ empty sym ]

>> s=dsolve('Dy=-2*2.825678*10^-7*x*Dx','22050000*sin(atan(Dy/Dx))/(7056000-7500*t)-1.624=-5.652*10^-7*Dx^2-6.652*10^-1442537.6*cos(atan(Dy/Dx))/(7056000-7500*t)')
Warning: Explicit solution could not be found.
> In dsolve at 197

s =

[ empty sym ]
是不是就是无解啊！

这个好像是常微分方程组把，先建立一个调用式子的函数： function f=hanshu(y,x) f=[a(x(3)-x(2)); b(x(1)-0.5*sqrt(x(2)-c)); d(2.5-x(3))]; 然后： [x,y]=ode45('hanshu',[t_start,t_final],x0); plot(t,x); 把初值和区间写上。感觉你的x1应该是x(1)把。我也正好做长微分方程，有空加我qq724918113