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Topic: Help Needed in math
Replies: 25   Last Post: May 2, 2014 6:01 PM

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 William Elliot Posts: 2,451 Registered: 1/8/12
Re: Help Needed in math
Posted: Apr 30, 2014 5:50 AM

On Wed, 30 Apr 2014, konyberg wrote:
> On Wednesday, April 30, 2014 5:02:27 AM UTC+2, William Elliot wrote:
> >
> > > > Find the largest values of the integer a for which ax^2-5x-3 is negative for all values of x.
> > > set a = (5x + 3) / x^2 and find the minima of this function. This will, with

> > 5/x + 3/x^2
> > -5/x^2 - 6/x^3 = 0
> > -5x + -6 = 0
> > x = -6/5
> > a = (-6 + 3)/(36/25) = -25/12
> > Why does the minimum work?

> Are you asking me why it works?
Yes.

Date Subject Author
4/28/14 punisher
4/28/14 quasi
4/29/14 Peter Percival
4/29/14 Karl-Olav Nyberg
4/28/14 Peter Percival
4/29/14 William Elliot
4/29/14 Peter Percival
4/29/14 Karl-Olav Nyberg
4/29/14 Karl-Olav Nyberg
4/29/14 Karl-Olav Nyberg
4/29/14 Karl-Olav Nyberg
4/29/14 William Elliot
4/30/14 Karl-Olav Nyberg
4/30/14 William Elliot
4/30/14 Karl-Olav Nyberg
4/30/14 William Elliot
5/1/14 Karl-Olav Nyberg
5/1/14 William Elliot
5/1/14 quasi
5/2/14 William Elliot
5/2/14 quasi
5/2/14 William Elliot
5/2/14 snmpprotocol@gmail.com
5/2/14 quasi
5/2/14 Karl-Olav Nyberg
5/2/14 quasi