document.write( "Question 815260: prove: cos(3pi/4+x)cos(2pi+x)[cot(3pi/2-x)+cot(2pi+x)]=1 \n" ); document.write( "

Algebra.Com's Answer #490848 by Edwin McCravy(20056) $\"\"$ $\"About$

You can put this solution on YOUR website!

Sorry, that is not an identity.\r\n" );
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document.write( "Put calculator in radian mode, let x=1 radian. Calculate:\r\n" );
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document.write( "Put it in your TI exactly this way:\r\n" );
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document.write( "cos(3p/4+1)cos(2p+1)(1/tan(3p/2-1)+1/tan(2p+1))\r\n" );
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document.write( "and you get -1.161134824, not 1.\r\n" );
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document.write( "There has to be a typo. \r\n" );
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document.write( "Edwin

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