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#1 2019-01-27 02:15:03

Zeeshan 01
Member
Registered: 2016-07-22
Posts: 726

Last step

Finding point of inflection
Fx= 2/x-4/x^2
I take second derivative tesr that is
4(x-6)/x^4
And point of inflection is 6 but in book there is two point of inflection 2/9 ,6


M.M.Zeeshan.K

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#2 2019-01-27 06:56:39

bob bundy
Administrator
Registered: 2010-06-20
Posts: 8,496

Re: Last step

x = 6, y = 2/9 is a point of inflexion.  Cannot find any others.

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
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#3 2019-01-27 07:04:52

Grantingriver
Member
Registered: 2016-02-01
Posts: 129

Re: Last step

Your answer is correct, but you have made a mistake and misunderstood the book. The point of inflection is not x in fact any point is an ordered pain (x,y) so the value of x which you have found is the first component of the point of inflection and the second component (which is y) can be found by substituting x=6 in the original equation, so we have:


hence the point of inflection is (6,2/9) which is the answer found in your book. I hope that will help.

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