document.write( "Question 1132204: Show that\r
\n" ); document.write( "\n" ); document.write( "(a) (tanx - cosx)/sinxcosx = sec²x - cosec²x\r
\n" ); document.write( "\n" ); document.write( "(b) sin⁴x + cos⁴x = 1- 2sin²xcos²x \n" ); document.write( "
Algebra.Com's Answer #749155 by ikleyn(52853)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "            I just solved part (b) yesterday under this link\r
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\n" ); document.write( "\n" ); document.write( "            https://www.algebra.com/algebra/homework/Trigonometry-basics/Trigonometry-basics.faq.question.1132184.html\r
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\n" ); document.write( "\n" ); document.write( "            https://www.algebra.com/algebra/homework/Trigonometry-basics/Trigonometry-basics.faq.question.1132184.html\r
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\n" ); document.write( "\n" ); document.write( "            For your convenience, I repeat this solution below  ONE  MORE  TIME.\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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\n" ); document.write( "\n" ); document.write( "QED.\r
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\n" ); document.write( "\n" ); document.write( "Please do not post it again.\r
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\n" ); document.write( "\n" ); document.write( "Also,  in the future,  DO  NOT  POST  more than one problem per post.\r
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\n" ); document.write( "\n" ); document.write( "It is the  RULE,  the  REQUIREMENT  and the  POLICY  of this forum.\r
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