Question

Tìm `x`
`(2x-1)^3=4(2x-1)`

Giải chi tiết giúp e với ạ

Answer 1

`(2x - 1)^3 = 4(2x - 1)`

`=> (2x -1)^3 - 4(2x -1) = 0`

`=> (2x - 1) . (2x - 1)^2 - 4 . (2x - 1) = 0`

`=> (2x - 1) . [(2x - 1)^2 - 4] = 0`

`=> (2x - 1) . (2x - 1 - 2). (2x - 1 +2)= 0`

`=> (2x - 1) . (2x - 3) . (2x + 1) = 0`

`=> [(2x-1 = 0),(2x - 3 = 0),(2x + 1 = 0):}`

`=> [(2x = 1),(2x = 3),(2x = -1):}`

`=> [(x = 1/2),(x = 3/2),(x = -1/2):}`

Vậy: `x = 1/2 ; x = 3/2 ; x = -1/2`