`a,(x-1)^2=0`
`=> x-1=0`
`=> x=0+1`
`=> x=1`
Vậy `x=1`
`b,(x+2)^2=1`
`=> (x+2)^2=(±1)^2`
\(⇒\left[ \begin{array}{l}x+2=1\\x+2=-1\end{array} \right.\)
\(⇒\left[ \begin{array}{l}x=1-2\\x=-1-2\end{array} \right.\)
\(⇒\left[ \begin{array}{l}x=-1\\x=-3\end{array} \right.\)
Vậy `x={-1;-3}`
