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Wikipedia:Reference desk/Archives/Mathematics/2022 October 3

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October 3

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True or not?

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Is it true that if (a/b) = (c/d) where a>c and b>d that ab/cd = a2? I have tried with lot of examples and it came true each time. ExclusiveEditor Notify Me! 09:01, 3 October 2022 (UTC)[reply]

Try a=b=3, c=d=2. Then ab/(cd) = 9/4, which is not a2. Staecker (talk) 10:33, 3 October 2022 (UTC)[reply]
More generally: , so c is in the numerator, not the denominator. The inequalities do not enter at all. --Wrongfilter (talk) 11:57, 3 October 2022 (UTC)[reply]
So equality holds if and only if For example, when we have
Then
 --Lambiam 13:39, 3 October 2022 (UTC)[reply]