A=[1324]B=[a00b] AB=[a3a2b4b] BA=[a00b][1324]=[a3b2a4b] AB=BA only when a=b
Let A= ( … ) and B= ( … ), a, b ∈ N. Then
JEE Main 2006 — Mathematics Algebra
2006mcqmedium
Let A=(1324) and B=(a00b),a,b∈N. Then
Official previous-year question
Held on 30 Apr 2006 · Verified 6 Jul 2026.
Options
- A
there cannot exist any B such that AB = BA
- B
there exist more than one but finite number of B’s such that AB = BA
- C
there exists exactly one B such that AB = BA
- D
there exist infinitely many B’s such that AB = BA
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