Input differential equation coefficients
Example differential equation conversions
The table below shows sample equations and their normalized standard forms for both first and second order linear equations with constant coefficients.
| Equation type | Original equation | Standard form |
|---|---|---|
| First order | 2·dy/dx + 4·y = 10 | dy/dx + 2·y = 5 |
| First order | -3·dy/dx + 6·y = 9 | dy/dx - 2·y = -3 |
| Second order | 4·y″ + 8·y′ + 12·y = 0 | y″ + 2·y′ + 3·y = 0 |
| Second order | -5·y″ + 15·y′ - 10·y = 20 | y″ - 3·y′ + 2·y = -4 |
Formulas used by this standard form calculator
This tool rewrites linear differential equations so that the leading derivative has coefficient one and all other terms are normalized relative to this leading term.
- First order linear equation with constant coefficients: a·dy/dx + b·y = c. Standard form is dy/dx + P·y = Q, where P = b / a and Q = c / a for a ≠ 0.
- Second order linear equation with constant coefficients: a·y″ + b·y′ + c·y = d. Standard form is y″ + p·y′ + q·y = r, where p = b / a, q = c / a, and r = d / a for a ≠ 0.
- The calculator divides every term of the equation by the leading coefficient a, ensuring the highest derivative has unit coefficient.
- Normalized coefficients are rounded to the number of decimal places you specify, helping you present results in a consistent, readable form.
How to use this differential equation tool
- Select whether your equation is first or second order linear.
- Enter the coefficients exactly as they appear in your original equation.
- Choose how many decimal places you want for normalized coefficients.
- Click the Calculate standard form button to generate the normalized version.
- Review the original and standard forms, along with normalized coefficients in the result table.
- Export the result as a CSV file for spreadsheets or as a PDF snapshot for reports, homework, or documentation.
1. Why standard form matters in differential equations
Writing an equation in standard form makes patterns visible, simplifies comparison between models, and prepares the problem for analytical or numerical solution methods such as integrating factors or characteristic equations.
2. First order linear models and this calculator
For equations like a·dy/dx + b·y = c, the calculator isolates dy/dx and expresses coefficients as P and Q, matching textbook notation for first order linear differential equations and standard solution techniques.
3. Second order models and system behaviour
Second order equations appear in oscillations, circuits, and control systems. Normalizing a·y″ + b·y′ + c·y = d to y″ + p·y′ + q·y = r helps you link coefficients directly to damping, stiffness, and forcing parameters.
4. Working alongside other mathematics tools
After standardizing a model, you can continue analysis using related tools such as the quadratic equation to standard form calculator, which supports characteristic polynomials of second order systems.
5. Complex-valued solutions and companion calculators
When characteristic roots are complex, the complex number multiplicative inverse calculator can help with algebra in the complex plane while you work with sinusoidal or exponential solutions.
6. Logarithmic expressions in solving differential equations
Integrating factors and separable equations often produce logarithmic terms. You can simplify expressions using the logarithm sum and difference calculator, keeping algebra tidy when manipulating solution steps.
Frequently asked questions
1. Which equations can this calculator handle?
It supports first and second order linear differential equations with constant coefficients in the form a·dy/dx + b·y = c or a·y″ + b·y′ + c·y = d.
2. Does it solve the differential equation completely?
No, it only converts the equation into normalized standard form. This prepares the model for manual or separate symbolic or numerical solvers, but it does not compute the general solution itself.
3. Why must coefficient a be non-zero?
The coefficient a multiplies the highest derivative. If a is zero, the equation is no longer of the stated order and cannot be normalized by dividing through by a single leading coefficient.
4. How should I choose the decimal places setting?
Use fewer decimals for quick inspection and more decimals when you intend to reuse coefficients in downstream calculations. Four to six decimal places usually balances readability with numerical accuracy.
5. Can I enter negative or fractional coefficients?
Yes. The calculator accepts any real-valued coefficients, including negative and fractional values. It divides each term by a, so signs and magnitudes are preserved correctly in the normalized form.
6. What happens if I leave some fields empty?
Empty or non-numeric fields are treated as invalid input. The page shows an alert asking you to enter valid numeric values so the normalization process and exports remain mathematically consistent.
7. How can I save results for reports or homework?
After calculating, you can export the table as CSV for spreadsheets or as a PDF snapshot. Both options capture the original and standard forms together with normalized coefficients.