`2.(x-1)^2 = 8`
`(x-1)^2 = 8:2`
`(x-1)^2 = 4`
`(x-1)^2 =`\(\left(\pm2\right)^2\)
`@Th1:`
`x-1=2`
`x=2+1`
`x=3`
`@Th2:`
`x-1=-2`
`x=-2+1`
`x=-1`
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`(2x+1)^3 = 125`
`(2x+1)63 = 5^3`
`=> 2x+1=5`
`2x=5-1`
`2x=4`
`x=4:2`
`x=2`
_________________________________________
`(x-2)^5 = 243`
`(x-2)^5 = 3^5`
`=> x-2=3`
`x=3+2`
`x=5`