Thursday, November 13, 2008

hi*-*
Today, Dr.A discussed the Quadratic,Absolute Value and Rational Inequalities.
Hmm...before that Dr.A explained the equationagain,Camille perfectly explained it last day(similar thing)
if you want more info... or practice about Quadratic Inequalities ,just click the links below....





http://www.resources.mei.org.uk/sample/files/ascai2.htmlurces.mei.org.uk/sample/files/ascai2.html

http://www.algebra-online.com/quadratic-inequalities-1.htm

lets proceed to the critical numbers (where the function is undefined)....Rational Inequalities

ex..

x-1/(x-2)(x+3)<>

How many critical numbers are there in that equation?

Ans..

3 critical numbers (1,2,-3)

After we identified the Critical numbers were now ready to Graph it on the number line...



Decide which intervals include numbers that make x-1/(x-2)(x+3) negative by substituting any number .......


http://www.purplemath.com/modules/ineqrtnl.htm

let's try -4

just subtitute it to the equation x-1/(x-2)(x+3)

-4-1/(-4-2)(-4+3)===-5/6(negative)

try 0.....(positive)

try 3(positive)

the only number that satisfy the given inequality (first one) .....therfore the answer is...

(-infinity,-3),(1,2)

http://www.purplemath.com/modules/ineqrtnl.htm

Absolute value inequalities

lets solve this equation:



/x/<3



we are looking for those real numbers x whose distance from the origin is less than 3 units.


(-3,0] [0,3)







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