Just a quick question on a pretty simple inequality question:

Up to here is simple enough. Now if I take the reciprocal of both sides, I can't with the zero on the left had side, so would I just consider:

So ?

Thanks in advance

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- May 31st 2010, 07:55 AMcraigSimple Inequality
Just a quick question on a pretty simple inequality question:

Up to here is simple enough. Now if I take the reciprocal of both sides, I can't with the zero on the left had side, so would I just consider:

So ?

Thanks in advance - May 31st 2010, 08:01 AMnikhil
if 1/x>0 then

x should be >0 (because reciprocal of a positive number is always positve)

now if 1/x<2 then

x>1/2

see

1/x<2

(1/x)-2<0

(1-2x)/x<0

since x can't be 0 multiplying both side by x

1-2x<0

2x>1

x>1/2 - May 31st 2010, 08:08 AMHallsofIvy
Although is NOT "infinity", it is true that so you can write this as which is the same as just saying .

- May 31st 2010, 11:40 AMcraig
Ahh I get you, cheers for the replies.