Can a vector have direction angles 45 o , 60 o , 120 o .

Question

Philoid · Accepted Answer

We know that, If l, m, n are the direction cosine of a vector and α, β, γ are the direction angle, then –

l = cosα, m = cosβ, n = cosγ

And, l² + m² + n² = 1 …… (i)

∴ l = cos45°, m = cos60°, n = cos120°

Now, substituting l, m, n in equation (i), we get -

⇒ 1 = 1

⇒ L.H.S = R.H.S

∴ A vector can have direction angles 45^o, 60^o, 120^o.

Can a vector have direction angles 45o, 60o, 120o.