Question

Write the direction cosines of $x-$axis.

Answer 1

Find the direction cosines of $x-$axis:

Direction cosines shows the angle made by the line with respect to $x,y,z-$axes.

$x-$axis makes an angle $0°$ with $x-$axis , $90°$ with $y-$axis, $90°$with $z-$axis

So, the direction cosines of the $x-$axis are $\cos 0°,\cos 90°,\cos 90°$

Direction cosines of the $x-$axis are $1,0,0$.

Hence, the direction cosines of the $x-$axis are $1,0,0$.