document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=654119>Question 654119</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Evaluate each equation. Give exact values without a calculator. 1.cos 405<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #408678 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=408678\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Evaluate each equation. Give exact values without a calculator. 1.cos 405<BR>\n" );
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document.write( "Identity: cos(s+t)=cos s cos t-sin s sin t<BR>\n" );
document.write( "cos(405)=cos(135+270)=cos 135*cos 270-sin 135*sin 270<BR>\n" );
document.write( "cos 135=-&#8730;2/2<BR>\n" );
document.write( "cos 270=0<BR>\n" );
document.write( "sin 135=&#8730;2/2<BR>\n" );
document.write( "sin 270=-1<BR>\n" );
document.write( "cos 135*cos 270-sin 135*sin 270<BR>\n" );
document.write( "=-&#8730;2/2*0-&#8730;2/2*(-1)<BR>\n" );
document.write( "=0+&#8730;2/2<BR>\n" );
document.write( "=&#8730;2/2<BR>\n" );
document.write( "cos(405)=&#8730;2/2 </SPAN>\n" );
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