. 8(x+y) ³ - 27 (x - y)³ factorise plz answer it fast
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8(x + y)^3 - 27(x - y)^3
= (2(x + y))^3 - (3(x - y))^3
= (2x + 2y)^3 - (3x - 3y)^3
[Formula (a - b)^3 = (a - b)(a^2 + ab + b^2)]
= (2x + 2y - 3x + 3y)*((2x + 2y)^2 + (2x + 2y)*(3x - 3y) + (3x - 3y)^2)
= (-x + 5y)*(4x^2 + 4y^2 + 8xy +6x^2 - 6y^2 + 9x^2 + 9y^2 - 18xy)
= (-x + 5y)*(19x^2 - 10xy + 7y^2) ——> Answer
= (2(x + y))^3 - (3(x - y))^3
= (2x + 2y)^3 - (3x - 3y)^3
[Formula (a - b)^3 = (a - b)(a^2 + ab + b^2)]
= (2x + 2y - 3x + 3y)*((2x + 2y)^2 + (2x + 2y)*(3x - 3y) + (3x - 3y)^2)
= (-x + 5y)*(4x^2 + 4y^2 + 8xy +6x^2 - 6y^2 + 9x^2 + 9y^2 - 18xy)
= (-x + 5y)*(19x^2 - 10xy + 7y^2) ——> Answer
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