Four of the five parts numbered (a), (b), (c), (d) and (e) are exactly equal. Which of the parts is not equal to the other four? The number of that part is the answer.
Options:
(A) (2x + 3y) 2
(B) (2y x) 2 + y(16x + 5y)
(C) 4x(x + 2y) + y(4x + 9y)
(D) (2x + 2y) 2 + y(4x + 5y)
(E) (2x y) 2 + 8y(2x + y) OK. Let's think. Some random thoughts first:
Others are requal to 4x2 + 9y2 + 12xy. The answer: (B).