If a line makes `alpha,beta,gamma` with x,y,z axis respectively, then prove that `sin^2alpha+sin^2beta+sin^2gamma=2`

If alpha, beta, gamma are the directional angles that a line makes with x-axis, y-axis and z-axis respectively, then sin ^(2) a + sin ^(2) beta + sin ^(2) gamma =

If a line makes angles alpha ,beta , gamma with the co-ordinates axes, then cos 2alpha +cos 2beta +cos 2gamma is :

If a line in the space makes angle alpha,beta and gamma with the coordinates axes, then cos^2alpha+cos^2beta+cos^2gamma is equal to a)1 b)2 c)0 d)3

If a straight line makes angles alpha,beta,gamma with the coordinate axes, then (1-"tan"^(2)alpha)/(1+"tan"^(2)alpha)+1/("sec"2beta)-2"sin"^(2)gamma is equal to

If a straight line makes the angle 60^(@),45^(@)andalpha with X, Y and Z-axes respectively, then "sin"^(2)alpha is equal to

A line makes acute angles of alpha, beta and gamma with the co-ordinae axes such that cos alpha cos beta = cos beta cos gamma = (2)/(9) and cos gamma cos alpha = (4)/(9), then cos alpha + cos beta + cos gamma is equal to : a) (25)/(9) b) (5)/(9) c) (5)/(3) d) (2)/(3)