document.write( "Question 289780: use calculus to find the max and min of\r
\n" ); document.write( "\n" ); document.write( "x - 2*cos(x)\r
\n" ); document.write( "\n" ); document.write( "for the interval -2<= x <= 0
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Algebra.Com's Answer #209871 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
To find extrema, take the derivative and set it equal to zero.
\n" ); document.write( "\"f%28x%29=x-2%2Acos%28x%29\"
\n" ); document.write( "\"df%2Fdx=1-2%2A%28-sin%28x%29%29=1%2B2%2Asin%28x%29=0\"
\n" ); document.write( "\"1%2B2%2Asin%28x%29=0\"
\n" ); document.write( "\"2%2Asin%28x%29=-1\"
\n" ); document.write( "\"sin%28x%29=-1%2F2\"
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-7%2C+1%2C+-10%2C+2%2C+x-2%2Acos%28x%29%29+\"
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\n" ); document.write( "\"sin%28x%29=-1%2F2\"
\n" ); document.write( "\"x=-pi%2F6\" and \"x=-5pi%2F6\"
\n" ); document.write( "From the graph, the maximum occurs at \"x=-5pi%2F6\",
\n" ); document.write( "\"f%28x%29=-5pi%2F6-2%2Acos%28-5pi%2F6%29\"
\n" ); document.write( "\"f%28x%29=-5pi%2F6-2%2A%28-sqrt%283%29%2F2%29\"
\n" ); document.write( "\"f%28x%29=-5pi%2F6%2Bsqrt%283%29%29\" or approximately
\n" ); document.write( "\"fmin=-0.886\"
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\n" ); document.write( "As you can see from the graph, solving for x only gives you the relative minimum and not the absolute minimum.
\n" ); document.write( "The absolute minimum occur at the endpoints.
\n" ); document.write( "\"fmin=f%28-2%2Api%29=-2%2Api-2%2Acos%282%2Api%29=-2%2Api-2=-8.28\"
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