Question

The area of the triangle having the points A(1,1,1), B(1,2,3), and C(2,3,1) as its vertices is

• A.
• B.
• C.
• D.

Answer 1

The correct option is C

$\frac{1}{2}|\overrightarrow{AB}\times \overrightarrow{AC}|=\frac{\sqrt{21}}{2}$