document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=635251>Question 635251</A>: <I><SPAN STYLE=\"word-break: break-all;\"> solve over the interval [0,2pi)<BR>\n" );
document.write( "2sin^2(x)+cos(x)-1=0 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #400213 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=400213\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> solve over the interval [0,2pi)<BR>\n" );
document.write( "2sin^2(x)+cos(x)-1=0<BR>\n" );
document.write( "----<BR>\n" );
document.write( "2(1-cos^2(x))+cos(x)-1 = 0<BR>\n" );
document.write( "2 - 2cos^2 + cos - 1 = 0<BR>\n" );
document.write( "----<BR>\n" );
document.write( "2cos^2 - cos -1 = 0<BR>\n" );
document.write( "Factor:<BR>\n" );
document.write( "(2cos+1)(cos-1) = 0<BR>\n" );
document.write( "cos(x) = -1/2 or cos(x) = 1<BR>\n" );
document.write( "x = (2/3)pi or x = (4/3)pi or x = 0<BR>\n" );
document.write( "============<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );