`***`Lời giải`***`
a)
`(x+2)^2=4`
`<=>x+2=\sqrt{4}`
`=>`\(\left[ \begin{array}{l}x+2=2\\x+2=-2\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}x=2-2\\x=-2-2\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}x=0\\x=-4\end{array} \right.\)
Vậy `x=0` hoặc `x=-4`
b)
`(x+3)^4=16`
`<=>`$x+3=\sqrt[4]{16} $
`=>`\(\left[ \begin{array}{l}x+3=2\\x+3=-2\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}x=2-3\\x=-2-3\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}x=-1\\x=-5\end{array} \right.\)
Vậy `x=-1` hoặc `x=-5`