Okay, I have a question that I am not good enough at multivariable calculus yet to answer myself.(adsbygoogle = window.adsbygoogle || []).push({});

Basically, say I have the following inequality:

a < sin(xy)/y < b

with a < b. How can I find out what the maximum value of y is on the interval 0 < y < 1 such that the above inequality holds for some x > 0?

That is, what is the biggest value of y between 0 and 1, such that for some x > 0, sin(xy)/y is between two limits a and b with a < b?

Is this even possible...?

Any information, hints, outright answers, scathing insults etc. would be appreciated! Thank you.

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# Using partial derivatives to find a maximum

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