document.write( "Question 139726: prove or disprove without a calculator.\r
\n" ); document.write( "\n" ); document.write( "1. sin(pi/2 + theta) = cos theta
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Algebra.Com's Answer #101845 by solver91311(24713)\"\" \"About 
You can put this solution on YOUR website!
Can't render theta on this site, so I'll use something else\r
\n" ); document.write( "\n" ); document.write( "\"sin%28alpha%2Bbeta%29=sin%28alpha%29cos%28beta%29%2Bcos%28alpha%29sin%28beta%29\"\r
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\n" ); document.write( "\"sin%28pi%2F2%2Bx%29=sin%28pi%2F2%29cos%28x%29%2Bcos%28pi%2F2%29sin%28x%29\", but \"sin%28pi%2F2%29=1\" and \"cos%28pi%2F2%29=0\", so\r
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\n" ); document.write( "\n" ); document.write( "\"sin%28pi%2F2%2Bx%29=1%2Acos%28x%29%2B0%2Asin%28x%29=cos%28x%29\"
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