Given: a=i^+2j^+k^, b=3(i^−j^+k^), a⋅c=3 and a×c=b.
Now, a×c=b
⇒(a×c)⋅b=∣b∣2
⇒(a×c)⋅b=(312+12+12)2
⇒(a×c)⋅b=27
⇒a⋅(c×b)=27...(i)
asa⋅(c×b)=b⋅(a×c)
Also, a⋅b=3−6+3=0
⇒a⋅((c×b)−b−c)=a⋅(c×b)−a⋅b−a⋅c
⇒a⋅((c×b)−b−c)=27−0−3
⇒a⋅((c×b)−b−c)=24
If a=i^+2j^+k^,b=3(i^−j^+k^) and c be the vector such that a×c=b and a⋅c=3, then a⋅((c×b)−b−c) is equal to
Held on 27 Jan 2024 · Verified 6 Jul 2026.
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