a) (5x-y)2 = (5x)2 - 2.5x.y + y2 = 25x2 - 10xy +y2
b) (2x + y2 )3 = (2x)3 - 3.(2x)2.y2 + 3.2x.(y2)2 - (y2)3 = 8x3 - 12x2y2 + 6xy4 - y6
c) (x + \(\dfrac{1}{4}\))2 = x2 + 2.x.\(\dfrac{1}{4}\) + (\(\dfrac{1}{4}\))2 = x2 + \(\dfrac{1}{2}\).x + \(\dfrac{1}{16}\)
d) (\(\dfrac{2}{3}\)x2 - \(\dfrac{1}{2}\)y)3 = (\(\dfrac{2}{3}\)x2)3 - 3.(\(\dfrac{2}{3}\)x2)2. \(\dfrac{1}{2}\)y + 3.\(\dfrac{2}{3}\)x2. ( \(\dfrac{1}{2}\)y)2 - (\(\dfrac{1}{2}\)y)3
= \(\dfrac{8}{27}\)x6 - \(\dfrac{2}{3}\)x4y + \(\dfrac{1}{2}\)x2y2 - \(\dfrac{1}{8}\)y3
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