Skip to content
Calcrivo

Separable Equation Solver

Solve separable first-order ODEs dy/dx = g(x)·h(y) numerically with RK4.

Inputs

Function of x only.

Function of y only. dy/dx = g(x)·h(y).

y(target x)

1.64872127

Steps used

200

Step by step

  1. Values used

    g(x) factor = x; h(y) factor = y; Initial x₀ = 0; Initial y₀ = 1; Target x = 1; Steps = 200

  2. Separable form

    dy/dx = g(x) · h(y)

  3. Analytical approach

    ∫ dy/h(y) = ∫ g(x) dx + C

  4. y(target x)

    = 1.64872127

  5. Steps used

    = 200

How it works

A separable ODE has the form dy/dx = g(x)·h(y), meaning the right-hand side factors into a function of x alone times a function of y alone. Theoretically, ∫dy/h(y) = ∫g(x)dx + C. This calculator solves it numerically using RK4, which works even when the antiderivatives have no closed form. Enter g(x) using x, and h(y) using x or y as the variable.

Formulas

Separable form

dy/dx = g(x) · h(y)

g(x)
Function of x only
h(y)
Function of y only

Analytical approach

∫ dy/h(y) = ∫ g(x) dx + C

C
Integration constant from initial condition

Frequently Asked Questions

What makes an ODE separable?

An ODE is separable when dy/dx can be written as a product of a function of x alone and a function of y alone: dy/dx = g(x)·h(y).

Why use numerical methods for separable equations?

While separable equations can theoretically be solved by integration, the integrals may not have closed-form solutions. Numerical methods always work.

You might also need