Friday, January 30, 2015

For what values of t does the inequality hold? 5-3l 2t-3l

Given the inequality:


 5 - 3
l 2t -3 l < -16


First, we will solve the way we
solve any equation.


We need to isolate the absolute values
on the left side.


Let us subtract 5 from both
sides.


==> -3 l 2t -3 l <
-16-5


==> -3 l 2t -3 l <
-21


Now we will divide by -3 and reverse the
inequality.


==> l 2t -3 l >
-21/-3


==> l 2t -3 l >
7


Now we have two
cases:


Case(1):


(2t -3 )
> 7


==> 2t >
10


==> t >
5


==> t = (5,
inf)..............(1)


Case(2):


-(2t-3)
> 7


==> -2t +3 >
7


==> -2t >
4


==> t <
-2


==> t= (-inf,
-2)............(2)


From (1) and (2) we conclude
that:


t= (-inf, -2) U (5,
inf)


OR:


t=
R- [ -2, 5]

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