Recent content by nikcs123

Thank you arkajad. (\vec{a}\times\vec{b})\times\vec{c}=\vec{a}\times(\vec{b}\times\vec{c}) Working with the left side, (\vec{a}\times\vec{b})\times\vec{c}=-\vec{c}\times(\vec{a}\times\vec{b})=\vec{c}\times(\vec{b}\times\vec{a}) So then...

cross product "associative triples" Homework Statement We know that the cross product is not associative, i.e., the identity (1) (\vec{a}\times\vec{b})\times\vec{c} = \vec{a}\times(\vec{b}\times\vec{c}) is not true in general. However, certain special triples \vec{a};\vec{b};\vec{c} of...

Ok so fixing the directions on the vectors I find that: V2 = \frac{\vec{AD}\times\vec{AB}}{2} V3 = \frac{\vec{AC}\times\vec{AD}}{2} V4 = \frac{\vec{BD}\times\vec{BC}}{2} (AB x AC) + (AD x AB) + (AC x AD) + (BD x BC) = 0 So I understand that the 3 vectors of a triangle put together...

Homework Statement Given a general (not necessarily a rectangular) tetrahedron, let V1, V2, V3, V4 denote vectors whose lengths are equal to the areas of the four faces, and whose directions are perpendicular to these faces and point outward. Show that: V1 + V2 + V3 + V4 = 0. The Attempt...