To calculate definite integral by the rectangle method, trapezoid method, Simpson method or other Newton-Cotes quadrature methods.

This online calculator builds Lagrange polynomial for a given set of points, shows a step-by-step solution and plots Lagrange polynomial as well as its basis polynomials on a chart. Also, it can interpolate additional points, if given

This online calculator builds a regression model to fit a curve using the linear least squares method. If additional constraints on the approximating function are entered, the calculator uses Lagrange multipliers to find the solutions.