The CompleteSquare(f, x) command, where f is a quadratic expression, equation, or an inequality in x, completes the square of f.  If f is not itself quadratic in x, its subexpressions are examined, and any which are quadratic in x are transformed to completed square form.

If x is a list or set, the operation of completing the square is applied successively to each component of x.  These components can be names, such as  and , or functions, such as  and .

The CompleteSquare(f) command is equivalent to CompleteSquare(f, indets(f,name)).

The command CompleteSquare(f, [x, y]) is equivalent to the command CompleteSquare(f, x, y).

The completed square form of the general quadratic expression  is .