matlab微分方程

来源:百度知道 编辑:UC知道 时间:2024/09/12 17:27:08
soln_1 = dsolve('Dy = 3*x^2','y(2)=0.5')

soln_1 =

3*x^2*t-6*x^2+1/2

soln_3 = dsolve('Dy = 3*y + exp(2*x)',' y(0) = 3')

soln_3 =

-1/3*exp(2*x)+exp(3*t)*(1/3*exp(2*x)+3)
为什么全和答案不一样 那个t是什么东西

它在dsolve中默认的变量为t,所以会出现这样的结果,你需要指定变量为x,或者你把你的x换成t,然后把结果中的t在换成x

正如楼上所言,dsolve默认自变量为t.

>> soln_1 = dsolve('Dy = 3*t^2','y(2)=0.5')

soln_1 =

t^3-15/2

>> soln_3 = dsolve('Dy = 3*y + exp(2*t)',' y(0) = 3')

soln_3 =

(-exp(-t)+4)*exp(3*t)

%替换
>> soln_3=subs(soln_3,'t','x')

soln_3 =

(-exp(-x)+4)*exp(3*x)