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Example 7

Find the unit vector and direction cosines of the given vector.

First find the length, then the unit vector, and then the direction cosines.

(a) A = 2i + j


Unit vector = 10_vectors-53.gif

Direction cosines =10_vectors-54.gif

(b) B = 5i - 12j


Unit vector = 10_vectors-56.gif

Direction cosines = (5/13, -12/13).

(c) C = j


Unit vector = 10_vectors-58.gif = j

Direction cosines = (0, 1).

Last Update: 2006-11-15