document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1019431>Question 1019431</A>: <I><SPAN STYLE=\"word-break: break-all;\"> To prove<BR>\n" );
document.write( "sin(theta+60)+sin(theta-60)=sin(theta)\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 #635373 by </B><A HREF=/tutors/aboutme.mpl?userid=fractalier><B>fractalier(6550)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=fractalier><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=fractalier><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=635373\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> To prove<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%28theta%2B60%29%2Bsin%28theta-60%29=sin%28theta%29 ALIGN=MIDDLE  ALT=\"sin%28theta%2B60%29%2Bsin%28theta-60%29=sin%28theta%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "expand sum and difference formulas and get<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28sin%28theta%29cos%2860%29+%2B+sin%2860%29cos%28theta%29%29%2B%28sin%28theta%29cos%2860%29+-+sin%2860%29cos%28theta%29%29+=+sin%28theta%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "You can see that the 2nd and 4th terms cancel out...we get<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%28theta%29cos%2860%29+%2B+sin%28theta%29cos%2860%29+=+sin%28theta%29 ALIGN=MIDDLE  ALT=\"sin%28theta%29cos%2860%29+%2B+sin%28theta%29cos%2860%29+=+sin%28theta%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Since cos 60 = 1/2, we get<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%28theta%29+=+sin%28theta%29 ALIGN=MIDDLE  ALT=\"sin%28theta%29+=+sin%28theta%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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