... = nên A 30 1, 5đ 1, 0đ x3 (1 − x) 2, f(x) = -> f (1- x) = x + (1 − x) x + (1 − x) -> f(x) + f (1 – x) = 1 2 -> x + y = -> f(x) + f(y) = 1, f = 1, 5đ 2 011 2 010 + f ... + f 2 012 + f 2 012 2 012 2 012 A= f 10 05 10 07 10 06 + + f 2 012 + f 2 012 + f 2 012 = 10 05 + = 10 05,5 ... 2c 5c + 2ca + 2a -> P ≤ ≤ 1, 5đ ≤ 1, 0đ 1, 0đ ( y + z) ≤ 1, 0đ ( 2z + x) ( 2x + y + y + z + 2z + x) = x + y + z 2 014 = -> Max P = 2 014 15 2 014 15 a = b = c = 15 2 014 1, 0đ Bài (6đ) a, BDE = BAE,...