document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=919589>Question 919589</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can someone please check my work?\r<BR>\n" );
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document.write( "The question says write the expression as sine, cosine or tan of a double angle and find exact value.\r<BR>\n" );
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document.write( "cos^2 60 -sin ^2 60\r<BR>\n" );
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document.write( "I got\r<BR>\n" );
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document.write( "Sin (120) which is sqrt 3 / 2.\r<BR>\n" );
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document.write( "Are you just supposed to add the two values?\r<BR>\n" );
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document.write( "thanks\r<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 #557838 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=557838\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The question says write the expression as sine, cosine or tan of a double angle and find exact value.<BR>\n" );
document.write( "cos^2 60 -sin ^2 60 <BR>\n" );
document.write( "Identity: cos(2x)=cos^2(x)-sin^2(x)<BR>\n" );
document.write( "cos^2 60 -sin ^2 60=cos(2*60)=cos(120&#730;) </SPAN>\n" );
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