document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=368274>Question 368274</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello Everyone please can you help with this\r<BR>\n" );
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document.write( "a) Find a vector which is perpendicular to the plane containing the vectors a=6i+k and b=2i+j\r<BR>\n" );
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document.write( "b) Find the area of the triangle with vertices at the points with coordinates (1,2,3),(4,-3,2) and (8,1,1)\r<BR>\n" );
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document.write( "Really wlould appreciate help on this one\r<BR>\n" );
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document.write( "Thanks<BR>\n" );
document.write( "Mick </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #262516 by </B><A HREF=/tutors/aboutme.mpl?userid=Fombitz><B>Fombitz(32388)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fombitz><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=Fombitz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=262516\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a) Use the cross product to find a vector perpendicular to both vector and the plane.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=V=AxB ALIGN=MIDDLE  ALT=\"V=AxB\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "V=(6,0,1)x(2,1,0)<BR>\n" );
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document.write( "b) Again use the cross product<BR>\n" );
document.write( "A:(1,2,3)<BR>\n" );
document.write( "B:(4,-3,2)<BR>\n" );
document.write( "C:(8,1,1)\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Area=%281%2F2%29%28ABxAC%29 ALIGN=MIDDLE  ALT=\"Area=%281%2F2%29%28ABxAC%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "where AB is the vector from A to B and AC is the vector from A to C.<BR>\n" );
document.write( "Check section 4.1 of http://en.wikipedia.org/wiki/Triangle for a derivation of this method.<BR>\n" );
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