Đáp án:
`(0,6)^6 . (x - 2/5) = (-2/5)^8`
`x - 2/5 = (-2/5)^8 : (0,6)^6`
`x - 2/5 = [(-2/5)^4]^2 : [(0,6)^3]^2`
`x - 2/5 = [16/625]^2 : [27/125]^2`
`x - 2/5 = [16/625 : 27/125]^2`
`x - 2/5= [16/135]^2`
`x - 2/5 = 256/18225`
`x = 256/18225 + 2/5`
`x = 7546/18225`