Question

can line have 60 degree,45 degree, 30 degree as it's direction angles

Answer 1

Given - 
                 Angles are 60 degree , 45 degree , 30 degree
                  We know -
                   cos² A +cos²B+cos² C  = 1
                    If A, B and C are direction angle of a line.
                       Here 
                     cos² (60) +cos²(45)+cos² (30) 
                     = 1/4 + 1/2 + 3/4  = 3/2 
                     So these are not direction angles of a line.