- ~The only courage that matters is the kind that gets you from one moment to the next~
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Mignon McLaughlin, The Second Neurotic's Notebook, 1966
Mignon McLaughlin, The
Second Neurotic's Notebook, 1966
Graphing Rational Functions
This is actually a tutorial of Chapter 9, Section 9-1
From the 1998 edition of the GLENCOE Algebra 2 book
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When a function has a RATIO OF TWO POLYNOMIAL EXPRESSIONS it is called a RATIONAL FUNCTION! |
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On this web page / means divided by. It will look like an underline in your textbook. |
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On this web page * means multiplied by. |
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An example of a rational function is X+1/(X+2)(X-5). |
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All RATIONAL FUNCTIONS have either F(X), G(X) or H(X) which means Y. When you graph the function on your calculator it will say Y= and then you can type the function. |
INSTRUCTIONS:
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Press the "ON" button on your calculator |
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Press the blue "Y=" button on your calculator |
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Let's graph the rational function X-2/X+3*X-8 |
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IMPORTANT HINT: always put your parentheses around everything that you type. Do double parentheses for when you have two problems back to back |
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Type: (X-2)/((X+3)(X-8)) |
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You're done! Remember that the "X" key looks like X,T,0,n and is next to the green alpha key |
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To finally complete everything, hit the graph button (one of the top five blue buttons at the top of the calculator). The answer you should get should look like two separate little graphs on one grid. |
A real example:
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Okay...here is a real example with a real graph. |
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Graph F(X)= X+3/X-2 |
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Type in this your y= : (X-3)/(X-2) and hit graph. |
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The vertical line that you see on the graph below will look like a solid line on your calculator but the answer is still the same. So don't panic. Just draw all the solid lines on your calculator as dotted lines on your paper. Your graphs should look somewhat similar to the one below! |
Your answer should look like this:
Still Confused? If yes, then go to any of the following pages for help:
On this website you can quiz yourself on your knowledge of graphing rational functions!
http://www.glencoe.com/sec/math/studytools/cgi-bin/msgQuiz.php4?isbn=0-02-825178-4&chapter=9&lesson=1
Get student made help on this website! Get help on ALL sorts of subjects!
http://www.mathpower.com/tutorial.htm
Ms. Blackwell's Website <-- the best website on the planet
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