The vectors are
and
.
Cross product of
and
is

Cross product of
and
is


.
The vectors
and
are orthogonal if and only if
.
The dot product of
and
is
.
Find the dot product of
and
.

.
Find the dot product of
and
.


Thus, the
is orthogonal to the both
and
.
.
is orthogonal to the both
and
.