What are the direction cosines of Z-axis?

Let a vector r make angles 60^(@), 30^(@) with X and Y -axis, respectively. What are the direction cosines of r ?

Write the direction cosines of Z-axis.

What are the direction cosines of the y-axis ?

Write the direction cosines of z-axis.

Write the direction cosines of x-axis.

Write the direction cosines of y-axis.

The direction cosines of z-axis are-