document.write( "Question 905071: given that sin A = 1 - sqrt(2) show that cos^2A +2SinA = 0 \n" ); document.write( "
Algebra.Com's Answer #549021 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"sin%28A%29+=+1+-+sqrt%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"sin%5E2%28A%29+=+%281+-+sqrt%282%29%29%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "\"sin%5E2%28A%29+=+%281+-+sqrt%282%29%29%281+-+sqrt%282%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"sin%5E2%28A%29+=+1%281+-+sqrt%282%29%29-sqrt%282%29%281+-+sqrt%282%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"sin%5E2%28A%29+=+1+-+sqrt%282%29-sqrt%282%29+%2Bsqrt%282%29%2Asqrt%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"sin%5E2%28A%29+=+1+-+2sqrt%282%29+%2B2\"\r
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\n" ); document.write( "\n" ); document.write( "\"sin%5E2%28A%29+=+3+-+2sqrt%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "-------------------------------------------------------\r
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\n" ); document.write( "\n" ); document.write( "\"1+-+sin%5E2%28A%29+=+cos%5E2%28A%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"1+-+%283+-+2sqrt%282%29%29+=+cos%5E2%28A%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"1+-+3+%2B+2sqrt%282%29+=+cos%5E2%28A%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-2+%2B+2sqrt%282%29+=+cos%5E2%28A%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"cos%5E2%28A%29+=+-2+%2B+2sqrt%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"cos%5E2%28A%29+%2B+2%2Asin%28A%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-2+%2B+2sqrt%282%29+%2B+2%2A%281+-+sqrt%282%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"-2+%2B+2sqrt%282%29+%2B+2+-+2%2Asqrt%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"0\"\r
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\n" ); document.write( "\n" ); document.write( "So this shows that \"cos%5E2%28A%29+%2B+2%2Asin%28A%29+=+0\" is true for every real number value of A. In other words, it is an identity.
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