About the Equation Solver
Solve almost any equation in x — polynomial, trigonometric, exponential or logarithmic — and find all real solutions in a range.
Also known as: solve equation, equation calculator, solve for x, root finder, find zeros of function.
How to use this calculator
- Enter equation, search from, search to.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
Rewrite as f(x) = 0 and locate every x where f changes sign
Worked example
Using the values pre-filled in the calculator above:
- Equation: x^3 - 2x = cos(x)
- Search from = -50
- Search to = 50
the calculator returns:
- Solutions (3): -1.3581687638, -0.5014946792, 1.4446705217
- Method: Numerical (sign changes + bisection)
Tips & common mistakes
- Periodic equations like sin(x) = 0.5 have infinitely many solutions; narrow the search range to see the ones you need.