Question

simplify : (3a -2b)³ - (3a + 2b)³​

Answer 1

Answer :

Let us assume, (3a - 2b) = x and (3a + 2b) = y.

x³ - y³

⇒ (x - y)(x² + xy + y²)

⇒ (3a - 2b - 3a - 2b){(3a - 2b)² +(3a - 2b)(3a + 2b) + (3a + 2b)²}

⇒ (-4b){9a² + 4b² - 12ab + 9a² - 4b² + 9a² + 4b² + 12ab}

⇒ (-4b)(27a² + 4b²)

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