document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=33173>Question 33173</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve: Arc sin 2x + Arc sin x = pi/2. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #19589 by </B><A HREF=/tutors/aboutme.mpl?userid=Fermat><B>Fermat(136)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fermat><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=Fermat><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=19589\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let A = asin(2x)<BR>\n" );
document.write( "Let B = asin(x)<BR>\n" );
document.write( "then<BR>\n" );
document.write( "A + B = pi/2<BR>\n" );
document.write( "cos(A+B) = cos(pi/2)<BR>\n" );
document.write( "cosAcosB - sinAsinB = 0<BR>\n" );
document.write( "cosAcosB - (2x)(x) = 0<BR>\n" );
document.write( "cosAcosB = 2x²<BR>\n" );
document.write( "cos²Acos²B = 4x^4<BR>\n" );
document.write( "(1-sin²A)(1-sin²B) = 4x^4<BR>\n" );
document.write( "(1-4x²)(1-x²) = 4x^4<BR>\n" );
document.write( "1 - x² - 4x² + 4x^4 = 4x^4<BR>\n" );
document.write( "1 - 5x² = 0<BR>\n" );
document.write( "5x² = 1<BR>\n" );
document.write( "x = 1/sqrt(5)<BR>\n" );
document.write( "============= </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );