document.write( "Question 762394: show that the vectors A = 3i - 2j +k , B= i - 3j + 5k , C= 2i + j - 4k form a right angled triangle. \n" ); document.write( "
Algebra.Com's Answer #463919 by MathLover1(20850)\"\" \"About 
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if
\n" ); document.write( "\"A+=+3i+-+2j+%2Bk\" ,
\n" ); document.write( "\"B=+i+-3j+%2B+5k\" ,
\n" ); document.write( "\"C=+2i+%2B+j+-+4k\" form a right angled triangle, then they satisfy Pythagorean theorem\r
\n" ); document.write( "\n" ); document.write( "\"C%5E2=A%5E2%2BB%5E2\"\r
\n" ); document.write( "\n" ); document.write( "if
\n" ); document.write( "\"A+=+3i+-+2j+%2Bk\" ,
\n" ); document.write( "\"B=+i+-3j+%2B+5k\" ,
\n" ); document.write( "\"C=+2i+%2B+j+-+4k\"\r
\n" ); document.write( "\n" ); document.write( "\"A%2BB+=+C\",
\n" ); document.write( "\"A\", \"B\"&\"C\" represents sides of the triangle\r
\n" ); document.write( "\n" ); document.write( "Then
\n" ); document.write( "\"A+=+sqrt%289+%2B4+%2B1%29=sqrt%2814%29\" units\r
\n" ); document.write( "\n" ); document.write( "\"B=+sqrt%281+%2B9+%2B+25%29=sqrt%2835%29\"\r
\n" ); document.write( "\n" ); document.write( "\"C=+sqrt%284+%2B+1+%2B16%29=sqrt%2821%29\"\r
\n" ); document.write( "\n" ); document.write( "since \"C%5E2=A%5E2%2BB%5E2\" = > \"%28sqrt%2835%29%29%5E2=%28sqrt%2814%29%29%5E2%2B%28sqrt%2821%29%29%5E2\"
\n" ); document.write( " = > \"35=14%2B21\"
\n" ); document.write( " = > \"35=35\" ...it's true, so the triangle is right angled triangle
\n" ); document.write( "
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