Question

1 - 8x^3

x^3 + 3x^2 +3x +1

(x+y)^2 -9x^2

10x -25 -x^2

8x^3- 1/8

1/25 x^2 -64x^2

-x^3 +9x^2 -27x +27 Giúp e với ạ

Answer 1

*) 1 - 8x³ = 1 - (2x)³

= (1 - 2x)(1 + 2x + 4x²)

*) x³ + 3x² + 3x + 1

= x³ + 3.x².1 + 3.x.1² + 1³

= (x + 1)³

*) (x + y)² - 9x²

= (x + y)² - (3x)²

= (x + y - 3x)(x + y + 3x)

= (y - 2x)(4x + y)

*) 10x - 25 - x²

= -(x² - 10x + 25)

= -(x² - 2.x.5 + 5²)

= -(x - 5)²

*) 8x³ - 1/8

= (2x)³ - (1/2)³

= (2x - 1/2)(4x² + x + 1/4)

*) 1/25 x² - 64x²

= -63,96x²

*) -x³ + 9x² - 27x + 27

= 27 - 27x + 9x² - x³

= 3³ - 3.3².x + 3.3.x² - x³

= (3 - x)³