document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1005145>Question 1005145</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Sin 20pi/9 * Cos 17pi/36 - Cos 20pi/9 * Sin 17pi/36\r<BR>\n" );
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document.write( "I tried the full equation Sin(A+B)and Sin(A-B) also for Cos but it won't work out. I think am doing something wrong with plugging it into the formula but it would never give me a degree on the unit circle. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #621451 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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/cgi-bin/show-face.mpl?user=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=621451\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font face=\"Times New Roman\" size=\"+2\">\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ \sin\alpha \cos\beta\ +\ \sin\beta \cos\alpha\ =\ \sin(\alpha\ +\ \beta)\">\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ \sin\frac{20\pi}{9}\cos\frac{7\pi}{9}\ +\ \sin\frac{7\pi}{9}\cos\frac{20\pi}{9}\ =\ \sin\left(\frac{20\pi}{9}\ +\ \frac{7\pi}{9}\right)\ =\ \sin\frac{27\pi}{9}\ =\ \sin 3\pi\">\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \ \ \ \ \ \ \ \ \ \ \sin k\pi\ =\ 0\ \forall\ k\ \in\ \mathbb{Z}\">\r<BR>\n" );
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document.write( "John<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE e^{i\pi}\ +\ 1\ =\ 0\"><BR>\n" );
document.write( "My calculator said it, I believe it, that settles it\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \ \\r\"> </SPAN>\n" );
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