Given that cos α ≠ 1, cos β ≠ 1, and cos γ ≠ 1, the vectors →a = i cos α + j cos β + k cos γ, →b = i + j cos β + k, and →c = i + j + k cos γ are

Vectors lying in the same plane
Vectors lying in the same plane if cos α = cos β = cos γ ≠ 1
Vectors lying in the same plane if cos α ≠ cos β ≠ cos γ
Vectors that are never in the same plane

Correct answer: Vectors lying in the same plane if cos α = cos β = cos γ ≠ 1

Solution

The vectors →a, →b, and →c are coplanar if cos α = cos β = cos γ ≠ 1, as this condition satisfies the coplanarity requirement, allowing the vectors to lie in the same plane.

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