document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=843799>Question 843799</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Prove that sin(alpha+beta)= sin alpha cos beta+cos alpha sin beta\r<BR>\n" );
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document.write( "I have no idea how to prove this. Please help! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #508364 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=508364\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The shortest way is to substitute <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\large \cos x = \frac{e^{ix} + e^{-ix}}{2}\"> and <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\large \sin x = \frac{e^{ix} - e^{-ix}}{2i}\"> and prove it algebraically. See the following article:\r<BR>\n" );
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document.write( "http://mathworld.wolfram.com/TrigonometricAdditionFormulas.html </SPAN>\n" );
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