Question

What are the direction cosines of X-axis?

Answer 1

$$\begin{gathered} \mathrm{The}x-\mathrm{axis}\mathrm{makes}\mathrm{angles}0°,90°\mathrm{and}90°\mathrm{with}\mathit{}x\mathit{,}\mathit{}y\mathrm{and}\mathit{}z\mathrm{axes},\mathrm{respectively}. \\ \mathrm{Therefore},\mathrm{the}\mathrm{direction}\mathrm{cosines}\mathrm{of}x-\mathrm{axis}\mathrm{are}\cos 0°,\cos 90°,\cos 90°,\mathrm{i}.\mathrm{e}.1,0,0. \end{gathered}$$