Given the function f (x + 2) = x & # 178; - x + 1, then f (x) is equal to

Given the function f (x + 2) = x & # 178; - x + 1, then f (x) is equal to

Let a = x + 2
x=a-2
So f (a) = (A-2) &# 178; - (A-2) + 1 = A & # 178; - 5A + 7
So f (x) = x & # 178; - 5x + 7