Đáp án:
` x ∈ { 1/4 ; -1/4 ; 3/4}`
Giải thích các bước giải:
`(2x - 1/2)^2 = (2x-1/2)^4 `
`<=> (2x - 1/2)^2 = (2x - 1/2)^2 . (2x - 1/2)^2 `
`<=> (2x - 1/2)^2 -(2x - 1/2)^2 . (2x - 1/2)^2 = 0`
`<=> (2x - 1/2)^2 . ( 1 - (2x - 1/2)^2 ) =0`
`<=> (2x - 1/2)^2 = 0 ; 1 - (2x - 1/2)^2 = 0 `
`<=> 2x-1/2 = 0 ; (2x-1/2)^2 = 1`
`<=> 2x = 1/2 ; 4x^2 - 2x + 1/4 - 1 = 0`
`<=> x = 1/4 ; 4x^2 - 2x -3/4 = 0 `
`<=> x = 1/4 ; (4x-3)(4x+1)=0`
`<=> x = 1/4 ; { 4x-3 = 0 ; 4x+1=0}`
`<=> x = 1/4 ; { x = 3/4 ; x=-1/4}`
Vậy` x ∈ { 1/4 ; -1/4 ; 3/4}`
xin ctlhn ạ
