. Is ab = 1 ?
(1) aba = a
(2) bab = b
Hi
I thought the answer was D) but turned ouy to be E).... can you please help?
section 19 #19
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You cannot cancel out a in (1) without knowing that a != 0. Think of itdunkin77 wrote:. Is ab = 1 ?
(1) aba = a
(2) bab = b
Hi
I thought the answer was D) but turned ouy to be E).... can you please help?
this way x * 0 = 0. Can you cancel out 0 from both sides and say x = 1?
No.
Same with b in (2).
Since we don't know that a!=0 and b!=0, the answer is E