Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
vector analysis dot product?
Given points a(2, 5, -1), b(3,-2,4) & c(-2,3,1).
Find:
(a) Rab "dot" Rac
(b) angle between Rab and Rac
(c) the length of the projection of Rab on Rac
(d) the vector projection of Rab on Rac
1 Answer
- HemantLv 710 years agoFavorite Answer
A(a↑) = (2,5,-1), B(b↑) = (3,-2,4), C(c↑) = (-2,3,1)
∴ (AB↑) = (b↑) - (a↑) = (3-2, -2-5, 4+1) = (1,-7,5)
∴ (AC↑) = (c↑) - (a↑) = (-2-2, 3-5, 1+1) = (-4,-2,2)
∴ (AB↑) · (AC↑) = (1)(-4) + (-7)(-2) + (5)(2) = 20
Then :
m∠ ( AB, AC ) = [ (AB↑) · (AC↑) ] / [ (AB) (AC) ] = ...
Proj of (AB↑) on (AC↑) = [ (AB↑) · (AC↑) ] / (AC) = ...
_______________________