Vector perpendicular to i^+j^+k^ and i^+2j^+3k^
=∣i^11j^12k^13∣=i^−2j^+k^
∴ Required projection
=∣i^−2j^+k^∣∣(2i^+3j^+k^)⋅(i^−2j^+k^)∣
=6∣2−6+1∣=63=23
JEE Main 2019 — Mathematics Vectors & 3D Geometry
The magnitude of the projection of the vector 2i^+3j^+k^ on the vector perpendicular to the plane containing the vectors i^+j^+k^ and i^+2j^+3k^, is:
Held on 8 Apr 2019 · Verified 6 Jul 2026.
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23
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23
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