The OA is E, I think it should be C
1) aba=a so a^2b-a=0
a(ab-1) = 0
so either a=0 or ab=1
2)
aba=b so b^2a-b=0
b(ab-1) = 0
so either b=0 or ab=1
combining 1 and 2, ab=1
Please help
Sec 19 Q17 DS1000
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- jayhawk2001
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Combining (1) and (2), we still have 2 options -- ab = 1, or (a=0, b=0)
Please note that (1) and (2) are both satisfied for a = 0, b = 0
Hence E
Please note that (1) and (2) are both satisfied for a = 0, b = 0
Hence E