Làm giúp tôi bài 10 câu 6-12 nhé

`6) 4a^2 - x^2 - 2x - 1`

`= (2a)^2- ( x^2 + 2x + 1 )`

`= ( 2a)^2 - ( x + 1 )^2`

`= ( 2a - x - 1 )( 2a + x + 1 )`

`7) 25a^2b^2 - 4x^2 + 4x - 1`

`= ( 5ab )^2 - ( 4x^2 - 4x + 1 )`

`= ( 5ab )^2 - ( 2x - 1 )^2`

`= ( 5ab - 2x + 1 )( 5ab + 2x - 1 )`

`8) 36x^2 - a^2 + 10a - 25`

`= ( 6x )^2 - ( a^2 - 10a + 25 )`

`= ( 6x )^2 - ( a - 5 )^2`

`= ( 6x - a + 5 )( 6x + a - 5 )`

`9) x^2 - 2x + 1 - a^2 - 2ab - b^2`

`= ( x - 1)^2 - ( a^2 + 2ab + b^2 )`

`= ( x - 1 )^2 - ( a + b )^2`

`= ( x - a - b - 1 )( x + a + b - 1 )`

`10) 1 - 2m + m^2 - x^2 - 4x - 4`

`= ( 1 - m )^2 - ( x^2 + 4x + 4 )`

`= ( 1 - m )^2 - ( x + 2 )^2`

`= ( 1 - m - x - 2 )( 1 - m + x + 2 )`

`= ( -m - x - 1 )( x - m + 3 )`

`=-( m + x + 1 )( x - m + 3 )`

`11) m^2 - 6m + 9 - x^2 + 4xy - 4y^2`

`= ( m - 3 )^2 - ( x^2 - 4xy + 4y^2 )`

`= ( m - 3 )^2 - ( x - 2y )^2`

`= ( m - 3 - x + 2y )( m - 3 + x - 2y )`

`12) 4x^2 - 4xy + y^2 - 25a^2 + 10a - 1`

`= ( 2x- y )^2 - ( 25a^2 - 10a + 1 )`

`= ( 2x - y )^2 - ( 5a - 1 )^2`

`= ( 2x - y - 5a + 1 )( 2x - y + 5a - 1 )`