`" If "(l,m,n)" are directional cosines of a line,then "cos^(2)alpha+cos^(2)beta+cos^(2)gamma=`

If (l,m,n) are the direction cosines of a line then cos^(2)alpha+cos^(2)beta+cos^(2)gamma=

Statement 1: If cos alpha,cos beta, and cos gamma are the direction cosines of any line segment,then cos^(2)alpha+cos^(2)beta+cos^(2)gamma=1. Statement 2: If cos alpha,cos beta,and cos gamma are the direction cosines of any line segment,then cos2 alpha+cos2 beta+cos2 gamma=1

If alpha, beta, gamma are direction angles of a line l, then prove that cos^(2)alpha+cos^(2)beta+cos^(2)gamma=1 . Hence, deduce that sin^(2) alpha + sin^(2) beta + sin^(2) gamma = 2 .

If alpha,beta ,gamma are direction angles of a line , then cos 2alpha + cos 2beta + cos 2 gamma =

If cos alpha, cos beta, cos gamma are the direction cosines of a line then the value of sin^(2) alpha + sin^(2) beta + sin^(2) gamma is__________

cos^(2) alpha +cos^(2) beta +cos^(2) gamma is equal to

If alpha, beta , gamma are direction-angles of a line, prove that (i) cos2alpha + cos 2 beta +cos2 gamma+ 1 = 0 . (ii) cos 2 alpha + cos 2 beta + cos 2 gamma = -1 .

If cosalpha,cosbeta,cosgamma are the direction cosines of a vector veca , then cos2alpha+cos2beta+cos2gamma is equal to