document.write( "Question 1132184: Show that\r
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Algebra.Com's Answer #749128 by ikleyn(52847)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "            I will solve the part  (b)  here only,  in a shorter way.\r
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document.write( "Start with\r\n" );
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document.write( "    \"sin%5E2%28x%29\" + \"cos%5E2%28x%29\" = 1.\r\n" );
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document.write( "Square both sides\r\n" );
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document.write( "    \"sin%5E4%28x%29\" + \"2%2Asin%5E2%28x%29%2Acos%5E2%28x%29\" + \"cos%5E4%28x%29\" = 1\r\n" );
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document.write( "Move the term  \"2%2Asin%5E2%28x%29%2Acos%5E2%28x%29\"  from the left side to the right, changing the sign\r\n" );
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document.write( "    \"sin%5E4%28x%29\" + \"cos%5E4%28x%29\" = 1 - \"2%2Asin%5E2%28x%29%2Acos%5E2%28x%29\".\r\n" );
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