Question

expand using suitable identities (x-2/3y)^3

Answer 1

(a-b)³ = a³- b³ - 3ab(a-b)

[(x-2)/3y]³
=(x-2)³/(3y)³
= x³ - 8 - 6x(x-2) / 27y³

Answer 2

Hi ,

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We know the identity ,

( a - b )³ = a³ - 3a²b + 3ab² - b³

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Here ,

(x-2/3y)³=x³-3x²(2y/3 )+3x(2y/3)²-(2y/3)³

= x³ - 2x²y + 4y²/3 - 8y³/27

I hope this helps you.

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