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Unformatted text preview: ne final example that we want to work here.
© 2007 Paul Dawkins 127 http://tutorial.math.lamar.edu/terms.aspx College Algebra Example 3 If -1 < x < 4 then determine a and b in a < 2 x + 3 < b .
This is easier than it may appear at first. All we are really going to do is start with the given
inequality and then manipulate the middle term to look like the second inequality. Again, we’ll
need to remember that whatever we do to the middle term we’ll also need to do to the two outer
So, first we’ll multiply everything by 2.
Now add 3 to everything. -2 < 2 x < 8
1 < 2 x + 3 < 11 We’ve now got the middle term identical to the second inequality in the problems statement and
so all we need to do is pick off a and b. From this inequality we can see that a = 1 and b = 11 . © 2007 Paul Dawkins 128 http://tutorial.math.lamar.edu/terms.aspx College Algebra Polynomial Inequalities
It is now time to look at solving some more difficult inequalities. In this section we will be
solving (single) inequaliti...
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This note was uploaded on 06/06/2012 for the course ICT 4 taught by Professor Mrvinh during the Spring '12 term at Hanoi University of Technology.
- Spring '12