b) \(\sqrt{x^2}=|-8|\)
\(\Rightarrow |x|=8\)
\(\Rightarrow x=\pm8\).
c) \(\sqrt{9x^2}=|-12|\)
\(\Rightarrow \sqrt{(3x)^2}=12\)
\(\Rightarrow |3x|=12\)
\(\Rightarrow 3x=\pm12\)
\(\Rightarrow x=\pm4\).
d) \(\sqrt{4-2\sqrt3}-\sqrt3=-1\)
\(VT= \sqrt{(\sqrt3)^2-2\sqrt3+1}-\sqrt3\)
\(=\sqrt{(\sqrt3-1)^2}-\sqrt3\)
\(=|\sqrt3-1|-\sqrt 3\)
\(=\sqrt 3-1-\sqrt3=-1=VP\)
