Question

Dados os vetores u= (1,2,3) e v=(-1,1,2), o produto vetorial UxV é igual a:

Answer 1

$\begin{array}{l}u\times v=\begin{vmatrix}i & j & k\\1 & 2 & 3\\-1 & 1 & 2\end{vmatrix}\\\\u\times v=4i-3j+k-( -2k+2j+3i) \ \ \ \text{( Regra\ de\ Sarrus)}\\\\\boxed{\boxed{u\times v=i-5j+3k=\langle 1,-5,3\rangle }}\end{array}$