Regula Falsi (False Position) Method Disadvantages

In numerical analysis, Regula Falsi method is one of the simplest and convergence guarenteed method for finding real root of non-linear equations. It is also known as False-Position method. Although it's convergence is guranteed, it has slow rate of convergence.

In this article, we are going to discuss various drawbacks of Regula Falsi method.


  1. Slow Rate of Convergence: Although convergence of Regula Falsi method is guaranteed, it is generally slow.
  2. Can not find root of some equations. For example: f(x) = x2 as there are no bracketing values.
  3. It has linear rate of convergence.
  4. It fails to determine complex roots.
  5. It can not be applied if there are discontinuities in the guess interval.
  6. It can not be applied over an interval where the function takes values of the same sign.