document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=756998>Question 756998</A>: <I><SPAN STYLE=\"word-break: break-all;\"> trigonometric equations:<BR>\n" );
document.write( " Solve: 1)sin^2x-4sinx+2=0<BR>\n" );
document.write( "2)2sin^2x-cos2x=0\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #460545 by </B><A HREF=/tutors/aboutme.mpl?userid=dkppathak><B>dkppathak(439)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=dkppathak><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=dkppathak><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=460545\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">   1)sin^2x-4sinx+2=0    let sin x =y<BR>\n" );
document.write( "   y^2-4y+2=0<BR>\n" );
document.write( "by completing perfect square we will factorize the equation<BR>\n" );
document.write( "y^2-4y+(2)^2-(2)^2+2=0\r<BR>\n" );
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document.write( "y^2-4y+4-4+2=0<BR>\n" );
document.write( "y^2-4y+4-2=0<BR>\n" );
document.write( "(y-2)^2-(sqrt2)^2=0<BR>\n" );
document.write( "(y-2-sqrt2)(y-2+sqrt2)=0<BR>\n" );
document.write( "y=2+sqrt2 or y=2-sqrt2<BR>\n" );
document.write( "sin x=2+sqrt2 or sin x=2-sqrt2  let 2+sqrt2=v1  and  2-sqrt2=v2<BR>\n" );
document.write( "x=2n pie+(-1)^n v1  or x=2n pie +(-1)^n v2<BR>\n" );
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