Question:
If $\overrightarrow{\mathrm{a}}=(-2 \hat{\mathrm{i}}-2 \hat{\mathrm{j}}+4 \hat{\mathrm{k}}), \overrightarrow{\mathrm{b}}=(-2 \hat{\mathrm{j}}+4 \hat{\mathrm{j}}-2 \hat{\mathrm{k}})$ and $\overrightarrow{\mathrm{c}}=(4 \hat{\mathrm{i}}-2 \hat{\mathrm{j}}-2 \hat{\mathrm{k}})$ then prove that $\overrightarrow{\mathrm{a}}, \overrightarrow{\mathrm{b}}$ and $\vec{C}$ are coplanar.
Solution:
