If OA vector and ob vector are not collinear, let om vector = λ OA vector + μ ob vector (λ, μ∈ R) prove: if a, B and m are collinear, then λ + μ = 1
Note: the following letters represent vectors
Since a, B and m are collinear, let am = t AB, then:
Om - OA = t (ob-oa) phase shift: om = t ob + (1-T) OA
Let λ = 1-T μ = t, then λ + μ = 1 is proved!
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