Q5 of 177 Page 24

A vector is inclined to the x - axis at 45o and y - axis at 60o. If units, find

Here, α = 45°,β = 60°,γ = θ (say)

l = cosα


= cos45°



m = cosα


= cos45°



n = cosθ


Now, substituting l, m,n in


l2 + m2 + n2 = 1,








∴ r⃗ = |r⃗ |( l î + m ĵ + n k̂)




⇒ r⃗ = 4(√2 î + ĵ± k̂)


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