document.write( "Question 1183181: Each of angles b/t the vectors u,v,& w is 60. ||u||= 4. . ||v||=2 & ||w||=6
\n" ); document.write( "Then find ||u+v+w||
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Algebra.Com's Answer #813383 by robertb(5830)\"\" \"About 
You can put this solution on YOUR website!
Use the fact that \"abs%28u%29%5E2+=+u%2Au+\" and \"u%2Av+=+abs%28u%29abs%28v%29cos%28theta%29\", where \"abs%28u%29\" is the magnitude of the vector \"u\", and \"u%2Av\" is the dot product of the vectors \"u\" and \"v\".\r
\n" ); document.write( "\n" ); document.write( "Then , by direct application of the distributive, commutative, and associative properties.\r
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\n" ); document.write( "\n" ); document.write( "= since \"theta%5B1%5D+=+theta%5B2%5D+=+theta%5B3%5D+=+60%5E0\"\r
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\n" ); document.write( "\n" ); document.write( "=, since \"cos60%5E0+=+1%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "= 16 + 4 + 36 + 8 + 12 + 24 = 100.\r
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\n" ); document.write( "\n" ); document.write( "==> \"abs%28u%2Bv%2Bw%29%5E2+=+100\" ===> \"highlight%28abs%28u%2Bv%2Bw%29+=+10%29\"
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