equivalent to x y + 2 x y (1 + y) 2 y

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equivalent to x y + 2 x y (1 + y) 2 y

by sanju09 » Wed Sep 15, 2010 3:21 am
Which of the following is equivalent to x y + 2 x y (1 + y) 2 y?
(A) x y (2 y + 1) ^2
(B) (2 x y + 1) (2 x y - 1)
(C) (2 x + y) ^2
(D) (x + 2 y) ^2
(E) y (x - 2 y) ^2


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by Rahul@gurome » Wed Sep 15, 2010 5:00 am
x y + 2 x y (1 + y) 2 y = xy[1 + 4y(1 + y)] = xy[4y^2 + 4y + 1] = xy[2y + 1]^2

The correct answer is[spoiler] (A)[/spoiler].
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by klmehta03 » Sun Sep 19, 2010 6:19 pm
Agree the ans is A

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by klmehta03 » Sun Sep 19, 2010 6:21 pm
Agree the ans is A

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by kaushiksin » Mon Sep 20, 2010 2:40 am
Answer is (A)

= xy (1+4y+4y^2)
= xy (2y+1)^2[/img]