document.write( "Question 1140452: Consider the function \"y+=+4sin%28expr%28pi%2F4%29%28x%29+-+pi%2F2%29+-+3\". Identify an interval starting at x = 2 with an average rate of change that is\r
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Algebra.Com's Answer #761054 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "The first obvious thing to do is use the identity \r\n" );
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document.write( "\"sin%28theta-pi%2F2%29=-cos%28theta%29\" to simplify.\r\n" );
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document.write( "\"y+=+4sin%28expr%28pi%2F4%29%28x%29+-+pi%2F2%29+-+3\" becomes\r\n" );
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document.write( "\"y+=+-4sin%28expr%28pi%2F4%29%28x%29%29+-+3\"\r\n" );
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document.write( "Its average (not instantaneous!) rate of change over \"P%3C=x%3C=Q\"\r\n" );
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document.write( "is  \r\n" );
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document.write( "which simplifies to\r\n" );
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document.write( "Then we use the identity: \"sin%28alpha%29-sin%28beta%29=2sin%28%28alpha-beta%29%2F2%29cos%28%28alpha%2Bbeta%29%2F2%29\"\r\n" );
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document.write( "I won't go through the details, but that simplifies to\r\n" );
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document.write( "Now you finish by solving this equality:\r\n" );
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document.write( "to find some zeros which will be answers to c) and which\r\n" );
document.write( "will also be critical numbers for a) and b).  Then solve this\r\n" );
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document.write( "for a)\r\n" );
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document.write( "and this\r\n" );
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document.write( "for (b)\r\n" );
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document.write( "Edwin
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