It is known that f (x) = | x + 1 | + | x + 2 | + +|x+2007|+|x-1|+|x-2|+… +|X-2007 | (x ∈ R), and f (a2-3a + 2) = f (A-1), then the value of a has () A. 2 b. 3 C. 4 d. countless

It is known that f (x) = | x + 1 | + | x + 2 | + +|x+2007|+|x-1|+|x-2|+… +|X-2007 | (x ∈ R), and f (a2-3a + 2) = f (A-1), then the value of a has () A. 2 b. 3 C. 4 d. countless

From the analytic expression of the function, f (- x) = f (x), so the function f (x) is even. Then from F (a2-3a + 2) = f (A-1), we can get a2-3a + 2 = A-1, or a2-3a + 2 = - (A-1) 2. From 1, we can get a = 1, or a = 3; from 2, we can get a = 1