document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=191792>Question 191792</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/1602773033/algebrahomeworkh>saxon algebra 2</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Evaluate cos^-1(square root 2/2) in both radians and degrees if it exists. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #143901 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=143901\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If you look at the unit circle:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" src=\"http://www.math.ucsd.edu/%7Ejarmel/math4c/Unit_Circle_Angles.png\">\r<BR>\n" );
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document.write( "You'll see that at the point on the circle that has the x-coordinate <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=sqrt%282%29%2F2 ALIGN=MIDDLE  ALT=\"x=sqrt%282%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > (in the first quadrant), the angle is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=pi%2F4 ALIGN=MIDDLE  ALT=\"pi%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > or 45 degrees.\r<BR>\n" );
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document.write( "So this means that <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \cos^{-1}\left(\frac{\sqrt{2}}{2}\right)=\frac{\pi}{4}\"> (in radians) or <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE \cos^{-1}\left(\frac{\sqrt{2}}{2}\right)=45\"> (in degrees) </SPAN>\n" );
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