A=[i−i−ii]
A2=[−222−2]=2[−111−1]
A4=22[2−2−22]=8[1−1−11]
A8=64[2−2−22]=128[1−1−11]
A8[xy]=[864]
⇒128[1−1−11][xy]=[864]
⇒128[x−y−x+y]=[864]
⇒x−y=161 ...(1)
and −x+y=21 ...(2)
⇒ From (1) and (2) : No solution.
JEE Main 2021 — Mathematics Algebra
Let A=[i−i−ii],i=−1. Then, the system of linear equations A8[xy]=[864] has :
Held on 16 Mar 2021 · Verified 6 Jul 2026.
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