Question

[Ý Cao]

Tính 

^: cái đó là dấu mũ nha!

1)(x+3) (x^2 - 3x +9)

2)(x^2 +2y)^2

3)(2x-3) (2x+3)

4)(x+3y)^3

5)(2x^2-y)^3

6)(x-3y) (x^2+ 3xy+ 9y^2)

7)(2x + 3y) (4x^2 - 6xy +9y^2)

8)(3x - y^2)^2

Giúp mình nha có j mình tích cho

Answer 1

[Linh_Chi_chimte]

1) (x+3)(x²- 3x + 9) = x³ + 27
2) (x² + 2y)² = x⁴ + 4xy + 4y² 
3) (2x-3)(2x+3) = 4x² - 9
4) (x + 3y)³ = x³ + 9x²y + 9xy² + y³
5) (2x²- y)³ = 8x⁶ - 6x⁴y + 6x²y² - y³
6) (x-3y)(x² + 3xy +9y²)= x³- 27y³
7) (2x + 3y)(4x² - 6xy +9y²)= 8x³ + 27y³
8) (3x - y²)²= 9x² - 6xy² + y⁴