Question

Matrice question about how rotation effects graphs. Easy question

Answer 1

use angle sum identity for sin and cos

cos(a+b) = cos(a)cos(b) - sin(a)sin(b)
sin(a+b) = sin(a)cos(b) + sin(b)cos(a)

where a = theta_1 and b=theta

Answer 2

does it mean the vector arrow goes closer to the y bar?

Answer 3

yes, vector rotates counter-clockwise so toward y-axis

Answer 4

ah yeh i know that

Answer 5

matrix R must be a 2 by 2 matrix
when you multiply R by [acos asin] you should end up with what i posted above

Answer 6

or just look at solution here :)
http://en.wikipedia.org/wiki/Rotation_matrix

Answer 7

wow awesome...i thought the question was too simple that it wouldn't be put on the web...just needed to visualise it to make sure