Answer:
[tex]f(n + 1) = f(n) - 2 \\ n = 1 - - - - f(1 + 1) =f(1) - 2 \: \: \: - - - > \: \: f(2) = 10 - 2 = 8 \\ f(2) = 8 \\ n = 2 - - - - f(2 + 1) = f(2) - 2 \: \: \: - - - > \: \: \: f(3) = 8 - 2 = 6 \\ so \: f(3) = 6 \\ and \: we \: are \: done.[/tex]