Suppose that \(T\) is a transformation of a complete metric space \(X\), and \(T^n\) (for a certain positive integer \(n\)) is a contraction with fixed point \(a\). Show that
- \(a\) is a fixed point of \(T\);
- \(T\) has only one fixed point;
- the sequence of successive iterations \(u_0\), \(u_1=Tu_0\), \(u_2=Tu_1,\ldots \) tends to \(a\) for any initial element \(u_0\in X\).