Chọn câu sai.

A. (x + 2y)³

B. (2x + y)³

C. (2x – y)³

D. (8x + y)³

A. (a – 3)²(a + 3)²

B. (a + 3)⁴

C. (a² + 36a + 9)(a² – 36a + 9)

D. (a² + 9)²

A. $(\frac{x}{2}+2y)(\frac{x^2}{2}+xy+2y^2)$

B. $(\frac{x}{2}+2y)(\frac{x^2}{4}-xy+4y^2)$

C. $(\frac{x}{2}+2y)(\frac{x^2}{2}-xy+4y^2)$

D. $(\frac{x}{2}+2y)(\frac{x^2}{4}-2xy+4y^2)$

A. (5x – 4)² – 49x² = -8(3x + 1)(x + 2)

B. (5x – 4)² – 49x² = (3x – 1)(x + 2)

C. (5x – 4)² – 49x² = -8(3x - 1)(x - 2)

D. (5x – 4)² – 49x² = -8(3x - 1)(x + 2)

A. 2x² + 8x + 8 

B. 2x² + 8x + 16

C. 4x² – 8x+ 16

D. 4x² + 8x + 16

A. (xy + 2)³

B. (xy + 8)³

C. x³y³ + 8   

D. (x³y³ + 2)³

A. (3x – 2y)² – (2x – 3y)² = 5(x – y)(x + y)

B. (3x – 2y)² – (2x – 3y)² = (5x – y)(x – 5y)

C. (3x – 2y)² – (2x – 3y)² = (x – y)(x + y)

D. (3x – 2y)² – (2x – 3y)² = 5(x – y)(x – 5y)