Câu trả lời:
a) ( x - 2) ( 2x + 1) = 8
8 = 1.8=8.1 =2.4=4.2=(-1).(-8)=(-8).(-1) =(-4) .(-2)= (-2).(-4)
x- 2 = 1 suy ra x= 3
2x + 1 = 8 suy ra 2x = 8- 1 = 7 suyra x= 7 : 2 suy ra x= 3, 5 ( loai cap nay )
x- 2 = 8 suy ra x= 10
2x+ 1= 1 suy ra 2x= 0 suy ra x=0
x- 2=2 suy ra x= 4
2x+ 1 = 4 suy ra 2x= 3 suy ra x= 1,5 ( loai cap nay )
x-2 = 4 suy ra x= 6
2x + 1 = 2 suy ra 2x= 1 suy ra x = 0,5 ( loai cap nay )
x-2=( - 1) suy ra x= 1
2x+ 1 = (-8) suy ra 2x = -9 suy ra x= -4,5 ( loai )
tuong tu cac cau tren ban tu giai nhe