Question

a, x^2-6x+9 b, 4x^2+4x+1 c, 1/4a^2+2ab+4b^2 d, 1/9-2/3y^4+y^8 e, 9x^2-15x+25/4 g, 36X^4+9x^2y+1/4y^2

Answer 1

`a, x^2-6x+9`

`= x^2-2*x*3+3^2`

`= (x-3)^2`

`b, 4x^2 + 4x+1`

`= (2x)^2 + 2*2x*1+1^2`

`= (2x+1)^2`

`c, 1/4a^2+2ab+4b^2`

`= (1/2a)^2 + 2*1/2a*2b+(2b)^2`

`= (1/2a+2b)^2`

`d, 1/9-2/3y^4+y^8`

`= y^8-2/3y^4+1/9`

`= (y^4)^2 - 2*y^4*1/3+(1/3)^2`

`= (y^4-1/3)^2`

Answer 2

a) x² - 6x + 9

= x² - 2.x.3 + 3²

= (x - 3)²

b) 4x² + 4x + 1

= (2x)² + 2.2x.1 + 1²

= (2x + 1)²

c) Sửa đề:

d)

  

Answer 3

`e, 9x^2 - 15x + 25/4`

`= (3x)^2 - 2*3x*5/2+(5/2)^2`

`= (3x-5/2)^2`

Sửa: `g, 36x^4 + 6x^2y + 1/4y^2`

`= (6x^2)^2 + 2*6x^2*1/2y+(1/2y)^2`

`= (6x^2+1/2y)^2`

Answer 4

e)

Answer 5

g) Sửa đề: