document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=664418>Question 664418</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How to prove the identity (sin^3@-cos^3@)/(sin@-cos@) = 1+sin@cos@\r<BR>\n" );
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document.write( "@=theta, I couldn't figure out how to use the symbol.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #413376 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=413376\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> How to prove the identity (sin^3@-cos^3@)/(sin@-cos@) = 1+sin@cos@ <BR>\n" );
document.write( "@=theta<BR>\n" );
document.write( "**<BR>\n" );
document.write( "(sin^3-cos^3)/(sin-cos)=1+sincos<BR>\n" );
document.write( "start with left side<BR>\n" );
document.write( "(sin^3-cos^3)/(sin-cos)<BR>\n" );
document.write( "difference of cubes<BR>\n" );
document.write( "=[(sin-cos)(sin^2+sincos+cos^2)]/(sin-cos)<BR>\n" );
document.write( "sin^2+cos^2=1<BR>\n" );
document.write( "=1+sincos<BR>\n" );
document.write( "verified: left side=right side<BR>\n" );
document.write( " </SPAN>\n" );
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