inequalities

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inequalities

by kashishh » Sat Jul 28, 2012 10:33 pm
i am always confused when i face an eqn like n-1<0
should i take n<1 or n>1

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by Birottam Dutta » Sat Jul 28, 2012 10:59 pm
if n-1<0 then n<1.

Can't be n>1.

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by alex.gellatly » Sat Jul 28, 2012 11:09 pm
kashishh wrote:i am always confused when i face an eqn like n-1<0
should i take n<1 or n>1
For adding and subtracting inequalities, just do the same thing you would do for algebra with an equal (=) sign, and keep the inequality sign unchanged. So...
n-1<0 is just;
n<1

Just move the 1 over like you would regularly do:
n-1=0
n=1

However, be careful with multiplication and division. You have to flip the sign if you multiply or divide by a negative number.