If `veca,vecb,vecc` are three coplanar vectors, then `[vecavecbvecc]` is

veca,vecb,vecc are three non zero vectors such that vecaxxvecb=vecc,vecbxxvecc=veca .Prove that veca,vecb,vecc are mutually at right angle and |vecb|=1,|vecc|=|veca| .

If veca, vecb, vecc are unit vectors then, veca.veca =_____

If veca,vecb,vecc are three vectors such that |veca|=5,|vecb|=12 and |vecc|=13 and veca+vecb+vecc=vec0 ,find the value of veca.vecb+vecb.vecc+vecc.veca .

If veca, vecb, vecc are unit vectors such that veca+vecb+vecc=0 , find the value of veca.vecb+vecb.vecc+vecc.veca .

Show that if veca+vecb,vecb+vecc,vecc+veca are coplanar then veca,vecb,vecc are also coplanar.

If veca,vecb,vecc are coplanar,prove that veca+vecb,vecb+vecc,vecc+veca are coplanar.

Show that the four points A, B, C and D with position vectors veca, vecb, vecc and vecd respectively are coplanar if 3 veca-2 vecb+vecc-2 vecd=0