document.write( "Question 1180906: F(x) =1/x^2 +18x+84
\n" ); document.write( "a) give the domain of f in interval novation
\n" ); document.write( "b) find the critical numbers
\n" ); document.write( "c) determine intervals where f is increasing and decreasing\r
\n" ); document.write( "\n" ); document.write( "Use the derivative test to determine
\n" ); document.write( "a) relative maxima
\n" ); document.write( "b) relative minima
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Algebra.Com's Answer #811106 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
\"F%28x%29+=1%2F%28x%5E2+%2B18x%2B84%29\"\r
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\n" ); document.write( "\n" ); document.write( "a) give the domain of f in interval novation\r
\n" ); document.write( "\n" ); document.write( "domain: \"r\" all real numbers (no matter what is \"x\", denominator will not be equal to zero\r
\n" ); document.write( "\n" ); document.write( "in interval novation:(\"-infinity\",\"infinity\")\r
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\n" ); document.write( "\n" ); document.write( "b) find the critical numbers\r
\n" ); document.write( "\n" ); document.write( "critical points are points where the function is defined and its derivative is zero or undefined\r
\n" ); document.write( "\n" ); document.write( "so, find derivative\r
\n" ); document.write( "\n" ); document.write( "\"F\"'\"%28x%29\" =\"%28d%2Fdx%29%281%2F%28x%5E2+%2B18x%2B84%29%29\"\r
\n" ); document.write( "\n" ); document.write( "\"F\"'\"%28x%29\" = \"-%282x+%2B+18%29%2F%28x%5E2+%2B+18+x+%2B+84%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"F\"'\"%28x%29\"=\"+-%282%28x+%2B+9%29%29%2F%28x%5E2+%2B+18+x+%2B+84%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "equal it to zero
\n" ); document.write( "\"0=+-%282%28x+%2B+9%29%29%2F%28x%5E2+%2B+18+x+%2B+84%29%5E2\"...will be zero if numerator equal to zero
\n" ); document.write( "\"0=+-2%28x+%2B+9%29\"
\n" ); document.write( "\"0=x+%2B+9\"
\n" ); document.write( "\"x+=-9\"\r
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\n" ); document.write( "\n" ); document.write( "c) determine intervals where f is increasing and decreasing
\n" ); document.write( "Use the derivative test to determine\r
\n" ); document.write( "\n" ); document.write( "if \"F\"'\"%28x%29%3E0\" f is increasing
\n" ); document.write( "if \"F\"'\"%28x%29%3C0\" f is decreasing\r
\n" ); document.write( "\n" ); document.write( "in your case
\n" ); document.write( "Increasing:(\"-infinity\",\"-9\")
\n" ); document.write( "Decreasing:(\"-9\",\"infinity+\"\r
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\n" ); document.write( "\n" ); document.write( "a) relative maxima
\n" ); document.write( "\"F%28x%29+=1%2F%28x%5E2+%2B18x%2B84%29\", substitute \"x+=-9\"
\n" ); document.write( "\"F%28x%29+=1%2F%28%28-9%29%5E2+%2B18%28-9%29%2B84%29\"
\n" ); document.write( "\"F%28x%29+=1%2F%2881+-162%2B84%29\"
\n" ); document.write( "\"F%28x%29+=1%2F3\"\r
\n" ); document.write( "\n" ); document.write( "max at (\"-9\",\"1%2F3\")\r
\n" ); document.write( "\n" ); document.write( "b) relative minima\r
\n" ); document.write( "\n" ); document.write( "no global minima found\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+600%2C+600%2C+-20%2C+5%2C+-5%2C+5%2C+1%2F%28x%5E2+%2B18x%2B84%29%29+\"\r
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