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#1 2006-03-07 17:33:44

ganesh
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Vectors

V # 1

Show that the vetcors a = (2,3,1), b = (5,-2,-4), and c = (10,-13,19) are mutually perpendicular.


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#2 2006-05-15 17:29:59

luca-deltodesco
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Re: Vectors

a dot b = cosine of angle between them, cosine of 90 degrees is 0, so if a dot b is 0, they are perpendicular

a dot b = 2*5 + 3*-2 + 1*-4 = 10-6-4 = 0, a,b are perpendicular
a dot c = 2*10 + 3*-13 + 1*19 = 20 - 39 + 19 = 0, a,c are perpendicular
b dot c = 5*10 + -2*-13 + -4*19 = 50 + 26 - 76 = 0, b,c, are perpendicular

Last edited by luca-deltodesco (2006-05-15 17:30:45)


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#3 2006-05-15 18:09:28

ganesh
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Re: Vectors

Very well done, luca-deltodesco!

http://www.geocities.com/aishwarya_82/images/greatworksmall.jpg


Character is who you are when no one is looking.
 

#4 2007-06-10 00:31:28

angel_12
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Re: Vectors

answer is already given...

waise that was a bit easy one!

 

#5 2007-11-07 08:16:27

mikau
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Re: Vectors

i'd like to demand lots of vector proof problems, please! smile

can't find enough of them.


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#6 2011-12-29 03:17:02

anonimnystefy
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Re: Vectors

hi ganesh

only one problem??? o.O


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