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Let =2 i+3 j+ k and q= i+2 j+ k be two vectors. If a vector =(α i+β j+γ k) is perpendicular to each of the vectors ( + q) and ( - q), and | |=√3,…

JEE Main 2021 — Mathematics Vectors & 3D Geometry

2021integermedium

Let p⃗=2i^+3j^+k^\vec{p}=2\hat{i}+3\hat{j}+\hat{k}p​=2i^+3j^​+k^ and q⃗=i^+2j^+k^\vec{q}=\hat{i}+2\hat{j}+\hat{k}q​=i^+2j^​+k^ be two vectors. If a vector r⃗=(αi^+βj^+γk^)\vec{r}=(\alpha \hat{i}+\beta \hat{j}+\gamma \hat{k})r=(αi^+βj^​+γk^) is perpendicular to each of the vectors (p⃗+q⃗)(\vec{p}+\vec{q})(p​+q​) and (p⃗−q⃗)(\vec{p}-\vec{q})(p​−q​), and ∣r⃗∣=3|\vec{r}|=\sqrt{3}∣r∣=3​, then ∣α∣+∣β∣+∣γ∣|\alpha |+|\beta |+|\gamma |∣α∣+∣β∣+∣γ∣ is equal to

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Held on 25 Jul 2021 · Verified 6 Jul 2026.

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