document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=937541>Question 937541</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the exact solutions of the given equation in the interval [0,2pi).<BR>\n" );
document.write( "cos2x+3cosx+2=0\r<BR>\n" );
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document.write( "a)x=2pi/3,pi,4pi/3<BR>\n" );
document.write( "b)x=0,pi/3,2pi/3,pi,4pi/3<BR>\n" );
document.write( "c)x=pi/2,7pi/6,11pi/6<BR>\n" );
document.write( "d)x=0<BR>\n" );
document.write( "e)x=0,pi/3,pi,5pi/3 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #570936 by </B><A HREF=/tutors/aboutme.mpl?userid=ewatrrr><B>ewatrrr(24785)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ewatrrr><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=ewatrrr><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=570936\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> cos2x+3cosx+2=0 <BR>\n" );
document.write( "2cos^2x - 1 + 3cosx + 2 = 0\r<BR>\n" );
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document.write( "2cos^2x + 3cosx + 1 = 0<BR>\n" );
document.write( "(2cosx + 1)(cosx + 1) = 0<BR>\n" );
document.write( "cosx = -1/2  0r cosx = -1<BR>\n" );
document.write( "....<BR>\n" );
document.write( "a)x=2pi/3 ,pi, 4pi/3<BR>\n" );
document.write( "........\r<BR>\n" );
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document.write( "(cosx, sinx) Summary Unit Circle<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/display-illustration.mpl?tutor=ewatrrr&illustration_name=wheel_smaller.jpg\">.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );