This linear algebra applet illustrates the formulae for the orthogonal projection of a vector onto a subspace. Such projections are widely used in applications of linear algebra, such as the least square problem.
Having an orthogonal basis in the subspace greatly simplifies the calculations: the output is the sum of the orthogonal projections on the coordinate axes.
This applet can also help students to gain geometric insight into the formula for the Fourier coefficients.
This is a modified version of the applet by Trefor Bazett.
