document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=672324>Question 672324</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please verify by changing the left side only:\r<BR>\n" );
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document.write( "tan(pi/4-x) = (cosx-sinx)/(cosx+sinx) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #417933 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=417933\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Please verify by changing the left side only: <BR>\n" );
document.write( "tan(pi/4-x) = (cosx-sinx)/(cosx+sinx)<BR>\n" );
document.write( "**<BR>\n" );
document.write( "Identity: tan(s-t)=(tan s-tan t)/(1+tan s tan t)<BR>\n" );
document.write( "tan(&#960;/4-x)=(tan &#960;/4-tan x)/(1+tan &#960;/4 tan x)<BR>\n" );
document.write( "tan &#960;/4=1<BR>\n" );
document.write( "=(1-tan x)/(1+tan x)<BR>\n" );
document.write( "=[1-(sin x/cos x)]/[1+(sin x/cos x)]<BR>\n" );
document.write( "=[(cos x-sin x)/cos x)]/[(cos x+sin x)/cos x)]<BR>\n" );
document.write( "cos x in denominator cancels out<BR>\n" );
document.write( "=(cos x-sin x)/(cos x+sin x)<BR>\n" );
document.write( "verified: left side=right side </SPAN>\n" );
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