Find the direction cosines of the following vectors : i. ii. iii.

Question

Philoid · Accepted Answer

(i)

Here,

The direction ratios of the vector 2 î + 2 j - k̂ are 2, 2, - 1

The direction cosines of the vector

∴ The direction cosines of are given by

(ii)

Here,

The direction ratios of the vector 6 î - 2 j - 3 k̂ are 6, - 2, - 3

The direction cosines of the vector

∴ The direction cosines of are given by

(iii)

Here,

The direction ratios of the vector 3 î - 4k̂ are 3, 0, - 4

The direction cosines of the vector

∴ The direction cosines of are given by