+) \(ax-a+bx-b+x-1=a\left(x-1\right)+b\left(x-1\right)+\left(x-1\right)\)
\(=\left(x-1\right)\left(a+b+1\right)\)
+) Xem lại đề
ax - a + bx - b + x - 1
= a( x - 1 ) + b( x - 1 ) + 1( x - 1 )
= ( x - 1 )( a + b + 1 )
x3 - 2x2 - 2x + 4 ( sửa -4 thành +4 )
= x2( x - 2 ) - 2( x - 2 )
= ( x - 2 )( x2 - 2 )
Bonus = ( x - 2 )[ x2 - ( √2 )2 ]
= ( x - 2 )( x - √2 )( x + √2 )