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]