Let f be a function satisfying f'(x) = -3xf(x), f(1) = 4 and lim x->infinity f(x) = 0.(adsbygoogle = window.adsbygoogle || []).push({});

Evaluate integral of -3x*f(x)*dx between 1 and infinity.

Does this have to do with using comparison properties or something? I really don't know where to start. Thanks for any help.

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# Don't know how to approach this one

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