... − x + x + 16 6, 4x −13 x + x − 18 a, x −5 x + d, x −13 x +36 8, − x − x + x + 7, x − x − x + b, 3x 8 x3+4 e, x +3 x − 18 9, 6x − x − 486 x 81 + 10, x − x − c, x +8 x +7 f, x −5 x −24 11, x3 − x ... + b vµ x2 + y2 = a2 + b2 TÝnh gi¸ trÞ cđa c¸c biĨu thøc sau : a) x3 + y3 ; b) x4 + y4 ; c) x5 + y5 ; d) x6 + y6 ; e) x7 + y7 ; f) x8 + y8 ; g) x20 08 + y20 08 Chuyªn ®Ị: Ph©n tÝch ®a thøc thµnh ... trÞ cđa biĨu thøc : A = a4 + b4 + c4 Cho x + y + z = vµ xy + yz + zx = TÝnh gi¸ trÞ cđa biĨu thøc : B = (x – 1)2007 + y20 08 + (z + 1)2009 – b2 = 4c2 Chøng minh r»ng : (5a – 3b + 8c)(5a – 3b – 8c)...