document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1044593>Question 1044593</A>: <I><SPAN STYLE=\"word-break: break-all;\">      | cosQ sinQ 0|<BR>\n" );
document.write( "A=   |-sinQ cosQ 0|<BR>\n" );
document.write( "     | 0     0   1|<BR>\n" );
document.write( "is invertible for all Q ,the find A^-1. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #659902 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=659902\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The rows (or columns) of A constitute an orthonormal set of vectors (i.e., any pair is orthogonal, or has scalar product 0; and each has magnitude 1.)  <BR>\n" );
document.write( "Therefore the inverse of A will just be its transpose <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%5ET ALIGN=MIDDLE  ALT=\"A%5ET\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "===> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%5E%28-1%29+=+A%5ET+=+%28matrix%283%2C3%2C+cosQ%2C+-sinQ%2C+0%2C+sinQ%2C+cosQ%2C+0%2C+0%2C0%2C1%29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "Feel free to verify that <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%2AA%5ET+=+A%5ET%2AA+=+I%5B3%5D ALIGN=MIDDLE  ALT=\"A%2AA%5ET+=+A%5ET%2AA+=+I%5B3%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" >. </SPAN>\n" );
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