document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=292706>Question 292706</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Use the sine and cosine addition formulæ to show that, for suitable x and y,\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=tan%28x%2By%29=%28tan%28x%29+%2B+tan%28y%29%29+%2F%281-tan%28x%29tan%28y%29%29 ALIGN=MIDDLE  ALT=\"tan%28x%2By%29=%28tan%28x%29+%2B+tan%28y%29%29+%2F%281-tan%28x%29tan%28y%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #211422 by </B><A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><B>Edwin McCravy(20056)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><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=Edwin+McCravy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=211422\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=tan%28x%2By%29=%0D%0A%0D%0Asin%28x%2By%29%2Fcos%28x%2By%29=+%28sin%28x%29cos%28y%29%2Bcos%28x%29sin%28y%29%29%2F%28cos%28x%29cos%28y%29-sin%28x%29sin%28y%29%29=%0D%0A%28%28sin%28x%29cos%28y%29%29%2F%28cos%28x%29cos%28y%29%29%2B%28cos%28x%29sin%28y%29%29%2F%28cos%28x%29cos%28y%29%29%29%2F%28%28cos%28x%29cos%28y%29%29%2F%0D%0A%28cos%28x%29cos%28y%29%29-%28sin%28x%29sin%28y%29%29%2F%28cos%28x%29cos%28y%29%29%29=%28%28sin%28x%29cross%28cos%28y%29%29%29%2F%0D%0A%28cos%28x%29cross%28cos%28y%29%29%29%2B%28cross%28cos%28x%29%29sin%28y%29%29%2F%28cross%28cos%28x%29%29cos%28y%29%29%29%2F%0D%0A%28%28cross%28cos%28x%29cos%28y%29%29%29%2F%28cross%28cos%28x%29cos%28y%29%29%29-%28sin%28x%29sin%28y%29%29%2F%28cos%28x%29cos%28y%29%29%29%0D%0A%0D%0A=+%28sin%28x%29%2Fcos%28x%29%2Bsin%28y%29%2Fcos%28y%29%29%2F%281-%28sin%28x%29%2Fcos%28x%29%29%28sin%28y%29%2Fcos%28y%29%29%29%0D%0A%0D%0A=+%28tan%28x%29%2Btan%28y%29%29%2F%281-tan%28x%29tan%28y%29%29%0D%0A%0D%0A ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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