This is LaTeX code:
[latex]
g_{1}(x) = |x-3| + 1\\ g_{2}(x) = 9^{\frac{2}{\pi}arcctg(x)}\\ g_{3}(x) = 9^{x}\\ f(x) = g_{3}(g_{2}(g_{1}(x)))
[/latex]