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April 8th, 2014, 04:49 PM  #1 
Newbie Joined: Apr 2014 From: Wellington Posts: 2 Thanks: 0  How do you solve this??
I have a point inside a square that needs to rotate from the center by a given angle normally 90,180,270 but I may in the future want it to rotate by another angle. So for example if I add 180degrees then the answer for a vector of (20,12) would change to (0, or if I add 270 it would change to (12,0). Ive been trying to solve for ages but am out of my depth. IF you could solve that would be great.. if you could also tell me what i should be reading to learn how to solve would be fantastic.. Thankyou for any help 
April 8th, 2014, 05:54 PM  #2 
Math Team Joined: Dec 2013 From: Colombia Posts: 7,671 Thanks: 2651 Math Focus: Mainly analysis and algebra 
Can you not move your square so that the centre is at the origin? It makes the rotation a little easier. As it is, I'd translate the centre to the origin, do the rotation and then translate it back again. 
April 8th, 2014, 06:21 PM  #3 
Newbie Joined: Apr 2014 From: Wellington Posts: 2 Thanks: 0  Yes I can
Yeah I can move it, Then I Could just add the size and width to move it back again aye? Thanks for your help.. 