If 
and 
are unit vectors forming an angle of 30o, find the area of the parallelogram having 
and 
as its diagonals.
Given two unit vectors
and
forming an angle of 30°.
We know the cross product of two vectors 
and 
forming an angle θ is
where 
is a unit vector perpendicular to
and 
.
Given two diagonals of parallelogram
and
Recall the area of the parallelogram whose diagonals are given by the two vectors 
and 
is
.
We have 
We have 
But, we found 
.
is a unit vector 
Thus, area of the parallelogram is 
square units.
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