document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1091318>Question 1091318</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How do I prove this identity?\r<BR>\n" );
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document.write( "1/1+cosx +1/1-cosx= 2/sin^2x </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #705679 by </B><A HREF=/tutors/aboutme.mpl?userid=math_helper><B>math_helper(2461)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_helper><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=math_helper><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=705679\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Please use parenthesis to make your question clear.   You must have meant:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+matrix%281%2C5%2C+1%2F%281%2Bcos%28x%29%29%2C+%22%2B%22+%2C1%2F%281-cos%28x%29%29%2C+%22=%22%2C+2%2F%28sin%5E2%28x%29%29+%29+ ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "—<BR>\n" );
document.write( "On left, multiply first term by (1-cos(x))/(1-cos(x)), 2nd term by (1+cos(x))/(1+cos(x)) :<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1%2F%281%2Bcos%28x%29%29+%2A+%281-cos%28x%29%29%2F%281-cos%28x%29%29++%2B++1%2F%281-cos%28x%29%29+%2A+%281%2Bcos%28x%29%29%2F%281%2Bcos%28x%29%29+=+2%2F%28sin%5E2%28x%29%29++ ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "—<BR>\n" );
document.write( "On left, multiply out numerator and denominator (its a common denominator due to the chosen multiplications):<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=++%281-cos%28x%29%29%2F%281-cos%5E2%28x%29%29+%2B+%281%2Bcos%28x%29%29%2F%281-cos%5E2%28x%29%29+=+2%2F%28sin%5E2%28x%29%29+ ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "simplifies to...<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=++++++2+%2F+%281-cos%5E2%28x%29%29++=+2%2Fsin%5E2%28x%29++ ALIGN=MIDDLE  ALT=\"++++++2+%2F+%281-cos%5E2%28x%29%29++=+2%2Fsin%5E2%28x%29++\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "The final step is to recognize that <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=++1-cos%5E2%28x%29+=+sin%5E2%28x%29+ ALIGN=MIDDLE  ALT=\"++1-cos%5E2%28x%29+=+sin%5E2%28x%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > and you are done. </SPAN>\n" );
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