document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=391229>Question 391229</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve the following equation for x:<BR>\n" );
document.write( "cos x = -1, for the interval 0 < x < 2 pi </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #277527 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=277527\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Look at a unit circle. For any point on the unit circle, the x-coordinate represents <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%28theta%29 ALIGN=MIDDLE  ALT=\"cos%28theta%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > and the y-coordinate represents <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%28theta%29 ALIGN=MIDDLE  ALT=\"sin%28theta%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "Since cos x = -1, the x-coordinate must be -1, and the y-coordinate must be 0 (due to the Pythagorean identity). This only occurs when <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+pi ALIGN=MIDDLE  ALT=\"x+=+pi\"   DISABLED_style= \"max-width:90%; height:auto;\" >. </SPAN>\n" );
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