Integrating Factor ODE dy/dx + y/(x + 4) = cos(x)
Multiplying by μ(x) = x + 4 yields exact derivative d/dx[(x+4)y] = (x+4)cos(x), solved alongside interactive RK4 trajectories.
Initial-Value Trajectory Summary (RK4 vs. Euler)
More ODE Slope Field Models
All trajectories exponentially approach horizontal equilibrium asymptote y = 1 regardless of initial temperature y(0).
dy/dx = -0.6*(y - 1)
Autonomous phase portrait contrasting unstable extinction equilibrium y = 0 against stable carrying capacity y = 3.
dy/dx = 0.8*y*(1 - y/3)
Initial states y(0) > 0 snap to upper attractor y = +2 while y(0) < 0 snap to y = −2, modeling Schmitt triggers and genetic switches.
dy/dx = 0.25*y*(4 - y^2)
Shows transient initial offset decaying away until all RK4 trajectories lock onto the same phase-lagged sinusoidal steady state.
dy/dx = 2*cos(1.8*x) - 0.9*y
Compares Euler’s 1st-order drift against 4th-order Runge–Kutta (RK4) across symmetric Gaussian peak trajectories.
dy/dx = -0.6*x*y
Non-separable quadratic ODE appearing in optimal LQR control theory and WKB quantum tunneling approximations.
dy/dx = 0.25*x^2 - 0.35*y^2