Factorise:
(i) 4x 2 + 9y 2 + 16z 2 + 12xy – 24yz – 16xz
(ii) 2x 2 + y 2 + 8z 2 – 2√2 xy + 4√2 yz – 8xz
The angle θ between the vectors \(\rm \vec{a} = 5\hat{i} - \hat{j} + \hat{k}\) and \(\rm \vec{b} = \hat{i} + \hat{j} - \hat{k}\) equals to
The equation $e ^{4 x}+8 e ^{3 x}+13 e ^{2 x}-8 e ^x+1=0, x \in R$ has :
If ABCD is a parallelogram, vector AB = 2i + 4j - 5k and vector AD = i + 2j + 3k, then the unit vector in the direction of BD is