\(a,\dfrac{2}{3}+\dfrac{1}{3}\times x^2=\left(-2\right)^0\)
\(\dfrac{2}{3}+\dfrac{1}{3}\times x^2=1\)
\(\dfrac{1}{3}\times x^2=1-\dfrac{2}{3}\)
\(\dfrac{1}{3}\times x^2=\dfrac{1}{3}\)
\(x^2=\dfrac{1}{3}:\dfrac{1}{3}\)
\(x^2=1\)
\(\Rightarrow x=\pm1\)
\(\dfrac{2}{3}+\dfrac{1}{3}.x^2=\left(-2\right)^0\)
\(\Leftrightarrow\dfrac{1}{3}.x^2=1-\dfrac{2}{3}\)
\(\Leftrightarrow\dfrac{1}{3}x^2=\dfrac{1}{3}\)
\(\Leftrightarrow x^2=1\)
\(\Leftrightarrow\left|x\right|=1\)
\(\Leftrightarrow\left[{}\begin{matrix}x=1\\x=-1\end{matrix}\right.\)