document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1208768>Question 1208768</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Prove (1  -  sin A)/(1 + sin A) = (sec A  -  tan A)^2 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #847208 by </B><A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><B>math_tutor2020(3817)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><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=847208\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=black size=3><BR>\n" );
document.write( "I'll transform the left hand side into the right hand side.<BR>\n" );
document.write( "For each step below, the right hand side stays the same.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281+-+sin%28A%29%29%2F%281+%2B+sin%28A%29%29+=+%28+sec%28A%29+-+tan%28A%29%29%5E2 ALIGN=MIDDLE  ALT=\"%281+-+sin%28A%29%29%2F%281+%2B+sin%28A%29%29+=+%28+sec%28A%29+-+tan%28A%29%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28%281+-+sin%28A%29%29%281+-+sin%28A%29%29%29%2F%28%281+%2B+sin%28A%29%29%281+-+sin%28A%29%29%29+=+%28+sec%28A%29+-+tan%28A%29%29%5E2 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply top and bottom of the left hand side by (1-sin(A))\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281-2sin%28A%29%2Bsin%5E2%28A%29%29%2F%281-sin%5E2%28A%29%29+=+%28+sec%28A%29+-+tan%28A%29%29%5E2 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281-2sin%28A%29%2Bsin%5E2%28A%29%29%2F%28cos%5E2%28A%29%29+=+%28+sec%28A%29+-+tan%28A%29%29%5E2 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F%28cos%5E2%28A%29%29-%282sin%28A%29%29%2F%28cos%5E2%28A%29%29%2B%28sin%5E2%28A%29%29%2F%28cos%5E2%28A%29%29+=+%28+sec%28A%29+-+tan%28A%29%29%5E2 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sec%5E2%28A%29-2%2A%281%2Fcos%28A%29%29%28sin%28A%29%2Fcos%28A%29%29%2Btan%5E2%28A%29+=+%28+sec%28A%29+-+tan%28A%29%29%5E2 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sec%5E2%28A%29-2sec%28A%29%2Atan%28A%29%2Btan%5E2%28A%29+=+%28+sec%28A%29+-+tan%28A%29%29%5E2 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28+sec%28A%29+-+tan%28A%29%29%5E2+=+%28+sec%28A%29+-+tan%28A%29%29%5E2 ALIGN=MIDDLE  ALT=\"%28+sec%28A%29+-+tan%28A%29%29%5E2+=+%28+sec%28A%29+-+tan%28A%29%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The identity has been confirmed.<BR>\n" );
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