Rieš v \( \R \) rovnicu:
\( \normalsize\sqrt{{x^2}+8}=2x+1 \)
\( \normalsize K=\left\{1\right\} \)
\( \normalsize K=\left\{2\right\} \)
\( \normalsize K=\left\{-1\right\} \)
\( \normalsize K=\left\{0\right\} \)