matlab中求二阶微分方程 的解析解和数值解,并在同一图形中画出解析解...答:y=dsolve('(1+x^2)*D2y=2*x*Dy','y(0)=1','Dy(0)=3',x)y = x*(x^2 + 3) + 1 数值解法:首先编写函数myfun.m function dy=myfun(x,y)dy=zeros(2,1)dy(1)=y(2);dy(2)=2*x*y(2)/(1+x^2)调用ode45:[x45,y45]=ode45('myfun',[0 10],[1 3])plot(x45,...