document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1016874>Question 1016874</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Let u and v be the vectors of length 3 and 5, respectively. Suppose u . v = 8. Find (-3u+4v) . (2u+5v).  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #633253 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=633253\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> u*u = square of the length of vector u, and <BR>\n" );
document.write( "v*V = square of the length of vector v.\r<BR>\n" );
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document.write( "==> (-3u+4v)*(2u+5v) = -6u*u-15u*v+8u*v+20v*v = -6*9 - 15*8 +8*8 +20*25 = 390. </SPAN>\n" );
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