query: Solve the PDE: $u_{xx} - 3u_{xt} - 4u_{tt} = 0$
positive_passages.docid: 9143
positive_passages.text: Solve $u_{xx}-3u_{xt}-4u_{tt}=0$ where $u(x,0)=x^2$ and $u_t(x,0)=e^x$
negative_passages.docid: 6937
negative_passages.text: General solution to the PDE $xU_x+yU_y=0$
negative_passages.docid: 36574
negative_passages.text: Does separation of variables in PDEs give a general solution?
negative_passages.docid: 14656
negative_passages.text: The differential equation $xu_{x}+yu_{y}=2u$ satisfying the initial condition $y=xg(x),u=f(x)$
negative_passages.docid: 123724
negative_passages.text: Solve $(y')^2 - xy' + y = 0$
negative_passages.docid: 35025
negative_passages.text: Solution to the linear SDE $dX_t = \alpha X_t \, dt + \sqrt{2} dB_t$ using Itô calculus
negative_passages.docid: 95774
negative_passages.text: $\frac{\partial^2 u}{\partial t^2}-c^2\frac{\partial^2u}{\partial x^2}=0\text{ implies } \frac{\partial^2 u}{\partial z \partial y}=0$
negative_passages.docid: 62211
negative_passages.text: Partial Differential Equation $U_t - (U_x)^2 = 0$
negative_passages.docid: 70460
negative_passages.text: How can I solve the following sequence
negative_passages.docid: 84689
negative_passages.text: solving third-order nonlinear ordinary differential equation
negative_passages.docid: 13829
negative_passages.text: PDE list of equations, derivative for boundarry condition evaluates to true
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negative_passages.text: Solve differential equation, $x'=x^2-2t^{-2}$
negative_passages.docid: 60396
negative_passages.text: How to Solve the Coupled Differential Equations?
negative_passages.docid: 137349
negative_passages.text: Solving Wave Equation with Initial Values
negative_passages.docid: 12869
negative_passages.text: Solving SDE: $dX(t) = udt + \sigma X(t)dB(t)$
negative_passages.docid: 114505
negative_passages.text: Initial value problem $t\frac{dx}{dt}=x+\sqrt{t^2+x^2}$
negative_passages.docid: 157624
negative_passages.text: How to force the function to take positive value when solving PDE by NDSolve