Yahoo Answers: Answers and Comments for Demand function differentiable, prove [pf(p)]'<0 iff p/f(p), f '( p) < 1.(revenue lowers if demand elastic )? [Mathematics]
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From Colince Lionel
enUS
Wed, 23 Nov 2011 12:28:26 +0000
3
Yahoo Answers: Answers and Comments for Demand function differentiable, prove [pf(p)]'<0 iff p/f(p), f '( p) < 1.(revenue lowers if demand elastic )? [Mathematics]
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https://answers.yahoo.com/question/index?qid=20111123122826AAVdcdF
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From Anonymous: [pf(p)]'=p'f(p)+pf'(p)=f(p)+pf'...
https://answers.yahoo.com/question/index?qid=20111123122826AAVdcdF
https://answers.yahoo.com/question/index?qid=20111123122826AAVdcdF
Wed, 30 Nov 2011 06:08:57 +0000
[pf(p)]'=p'f(p)+pf'(p)=f(p)+pf'(p)
[pf(p)]'<0 gives
f(p)+pf'(p)< 0
f(p)<  pf'(p)
or
pf'(p)/f(p) >1
or
multiplying by 1 on both sides
(p/f(p))*f'(p) <1
i believe thats wat the question was .