The two vectors \(\rm \left(\begin{array}{l}a \\ 0\end{array}\right)\ and\ \left(\begin{array}{l}b \\ c\end{array}\right)\) are orthonormal if
1
\(a= \pm 1, b= \pm 1 / \sqrt{2}, c= \pm 1 / \sqrt{2}\)
2
\(a= \pm 1, b= \pm 1, c=0\)
3
\(a= \pm 1, b=0, c= \pm 1\)
4
\(a= \pm 1, b= \pm 1 / 2, c=1 / 2\)