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#1 2009-11-05 11:17:38

Vercingetorix
Member
Registered: 2009-11-03
Posts: 21

Inequality Help

I am trying to solve

.

The text tells me that the answer is

,

Whereas I continue to arrive at

.

Can someone please shed some light on this?

Cheers.

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#2 2009-11-05 11:35:13

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

Re: Inequality Help

Don't forget, when you multiply an inequality by a negative number, you need to flip the sign as well.


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

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#3 2009-11-06 18:41:50

Anakin
Member
Registered: 2009-10-04
Posts: 145

Re: Inequality Help

You have to flip the signs when you multiply/divide both sides by a negative number. I'm just posting the above to show you that, but my process is not right.

The correct answer should be -1/10 < x < 0 OR 0 < x < 1/10. Plug in values and you will see that my answer is correct. For instance if what the text says about x having to be less than 1/10 was true, then that means we can sub a value like -2/10 in for x.

Which obviously is not correct.

Last edited by Anakin (2009-11-06 18:56:35)

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