A) (X4 + 8X2 + 16)

Bài 11: câu nào sai: a) (x

4

+ 8x

2

+ 16) : (x

2

+ 4) = x

2

+ 4 ; b) ( x

3

+1) : (x

2

- x+1) = x - 1 c) (25 - x

2

) : (x+5) = 5 – x ; d) 9(x - 2y)

10

: (3x –-6y) = 3(x- 2y)

9