Let \(\rm \vec{a}\), \(\rm \vec{b}\) and \(\rm \vec{c}\) be the position vectors of the three vertices A, B, C of a triangle respectively. Then the area of this triangle is given by:
1
\(\rm \dfrac{1}{2} (\vec{a}\times \vec{b})\vec{c}\)
2
\(\rm \dfrac{1}{2} |\vec{a}\times \vec{b} + \vec{b} \times \vec{c}+\vec{c}\times \vec{a}|\)
3
\(\rm \vec{a}\times \vec{b} + \vec{b} \times \vec{c} + \vec{c} \times \vec{a}\)
4
None of these