c=(∣b∣b⋅a)∣a∣a =(9λ+8)(i^+2j^+2k^)∣a+c∣=7⇒(9λ+8+1)i^+(92(λ+8)+2)j^+(92(λ+8)+2)k^=7(9λ+8+1)2+(92(λ+8)+2)2+(92(λ+8)+2)2=49 ⇒λ=4⇒c=34i^+38j^+38k^ Area of parallelogram =i^344j^380k^384=16
Let be the projection vector of b=λ i+4 k, λgt0, on the vector a= i+2 j+2 k. If | a+ |=7, then the area of the parallelogram formed by the vectors b…
JEE Main 2025 — Mathematics Vectors & 3D Geometry
Let c be the projection vector of b=λi^+4k^,λ>0, on the vector a=i^+2j^+2k^. If ∣a+c∣=7, then the area of the parallelogram formed by the vectors b and c is ________
Held on 22 Jan 2025 · Verified 6 Jul 2026.
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