Given, a=i+j−k and c=2i−3j+2k
b×c=a and ∣b∣∈1,2……10
∵b×c=a
⇒a is perpendicular to b as well as a is perpendicular to c , so a⋅c=0 as they are perpendicular.
Now checking a⋅c=2−3−2=−3=0
This b×c=a is not possible.
So, number of vectors b=0
Let a=i^+j^−k^ and c=2i^−3j^+2k^. Then the number of vectors b such that b×c=a and ∣b∣∈1,2,…,10 is
Held on 27 Jun 2022 · Verified 6 Jul 2026.
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