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#1 2007-11-16 05:45:08

tony123
Member
Registered: 2007-08-03
Posts: 197

minimum value

Find the minimum value of the function

.

Last edited by tony123 (2007-11-16 05:47:59)

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#2 2007-11-16 08:12:42

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: minimum value

Just by looking at it, the smallest I can see is 501, when x=-1.
No idea how to do it "properly" though.


Why did the vector cross the road?
It wanted to be normal.

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#3 2007-11-16 08:31:09

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

Re: minimum value

If x ≠ 1,

Indeed, as f(1) isn’t the mininum value, you might as well use this formula. Also it appears that f(x) is always positive, so you can probably ignore the modulus sign as well.

I then used differentiation and verified that f(−1) is the minimum value. Well, maybe there’s a less complicated way to do this.

Last edited by JaneFairfax (2007-11-16 08:31:40)

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