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**Zeeshan 01****Member**- Registered: 2016-07-22
- Posts: 720

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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**bob bundy****Administrator**- Registered: 2010-06-20
- Posts: 8,452

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

Bob

Children are not defined by school ...........The Fonz

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**Grantingriver****Member**- Registered: 2016-02-01
- Posts: 115

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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