Question

Show that area of the parallelogram whose diagonals are given by $\vec{a} \ and \ \vec{b}$ is $\frac{|\vec{a} \times \vec{b}|}{2}$ Also find the area of the parallelogram whose diagonals are $2\hat{i}-\hat{j}+\hat{k} \ and \ \hat{i}+3\hat{j}-\hat{k}.$

Answer 1

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