document.write( "Question 165212: Please assist me with the following problem:\r
\n" ); document.write( "\n" ); document.write( "Using the intermediate value theorem, determine, if possible, whether the function f has a real zero between a and b\r
\n" ); document.write( "\n" ); document.write( "f(x)=3x^2-2x-11; a=2, b=3
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Algebra.Com's Answer #121772 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Let's evaluate the left endpoint a=2\r
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\n" ); document.write( "\n" ); document.write( "\"f%28x%29=3x%5E2-2x-11\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"f%282%29=3%282%29%5E2-2%282%29-11\" Plug in \"x=2\".\r
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\n" ); document.write( "\n" ); document.write( "\"f%282%29=3%284%29-2%282%29-11\" Square \"2\" to get \"4\".\r
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\n" ); document.write( "\n" ); document.write( "\"f%282%29=12-2%282%29-11\" Multiply \"3\" and \"4\" to get \"12\".\r
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\n" ); document.write( "\n" ); document.write( "\"f%282%29=12-4-11\" Multiply \"-2\" and \"2\" to get \"-4\".\r
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\n" ); document.write( "\n" ); document.write( "\"f%282%29=-3\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "Let's evaluate the right endpoint b=3\r
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\n" ); document.write( "\n" ); document.write( "\"f%28x%29=3x%5E2-2x-11\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"f%283%29=3%283%29%5E2-2%283%29-11\" Plug in \"x=3\".\r
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\n" ); document.write( "\n" ); document.write( "\"f%283%29=3%289%29-2%283%29-11\" Square \"3\" to get \"9\".\r
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\n" ); document.write( "\n" ); document.write( "\"f%283%29=27-2%283%29-11\" Multiply \"3\" and \"9\" to get \"27\".\r
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\n" ); document.write( "\n" ); document.write( "\"f%283%29=27-6-11\" Multiply \"-2\" and \"3\" to get \"-6\".\r
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\n" ); document.write( "\n" ); document.write( "\"f%283%29=10\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So as x changes from 2 to 3, f(x) (ie y) changes from -3 to 10 which means that the graph MUST have crossed over the x-axis somewhere in between x=2 and x=3. So this shows that there is a zero between a and b
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