Question

The side length, s, of a cube is x – 2y. If V = s3, what is the volume of the cube? x3 – 6x2y + 12xy2 – 8y3 x3 + 6x2y + 12xy2 + 8y3 3x3 – 6x2y + 12xy2 – 24y3 3x3 + 6x2y + 12xy2 + 24y3

Answer 1

Answer: A.

Explanation:

Answer 2

V = x³ - 6x²y + 12xy² - 8y³

V = (x - 2y)³

= (x - 2y)(x - 2y)(x - 2y) ( expand first pair of factors )

= (x² - 4xy + 4y²)(x - 2y) ( multiply terms in first by terms in second )

= x³ - 4x²y + 4xy² - 2x²y + 8xy² - 8y³ ( collect like terms )

= x³ - 6x²y + 12xy² - 8y³