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February 22nd, 2015, 03:02 PM   #1
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Lengths and angles

a->= 3 b->= square root 2
<_ ( a->. b >) = 45 celsius
f) decide t so that (A -> + tb --->) _|_ (2a -> - b ->)

The book says the answer is t= - 15/4

The book says p-> _|_ q-> <-> P-> * q-> = 0

But in this case the answer dosent become 0. So i don't understand why _|_ in this case won't become cero

Last edited by Zman15; February 22nd, 2015 at 03:05 PM.
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February 22nd, 2015, 03:54 PM   #2
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Hello, Zman15!

It's hard to read your notation.
I'll guess what you mean.


Quote:


<_ ( a->. b >) = 45 Celsius

f) Decide so that:

The book says the answer is

The book says:

But in this case the answer doesn't become 0.






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February 22nd, 2015, 04:21 PM   #3
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Thanks for the answer i need a help with an other task : http://i1277.photobucket.com/albums/...psogbql2s2.jpg
The figure shows a-> = 2 and b-> = 3
I have a problem with task C) whict says BC> = a + b and decide | BC> |
The book says the answer is square root 19, and square root 19 = 4.35.
A + B = 2 + 3 = 5. And | BC | = BC ^ 2 = 5 ^ 2 = 25. Which would mean square root of 25 is 5.

Has the book given the wrong answer again?
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