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You are not logged in. #1 20121201 11:45:40
Question about rotationA square has coordinates (3, 2), (1, 3), (2, 1), and (2, 2). It is rotated so that: #2 20121201 12:22:46
Re: Question about rotationSuppose the centre of the rotation is (a,b). This rotation takes the point (2,−1) to (0,3). Then the same rotation about the origin would take the point (2−a,−1−b) to (−a,3−b). (And the other points correspondingly, but we only need one point to work out a and b.) Hence Solving the simultaneous equations gives . #3 20121201 19:40:00
Re: Question about rotationhi Sparky,
Yes. See diagram. You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #4 20121201 21:03:47
Re: Question about rotationHi Bob The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #5 20121201 22:15:09
Re: Question about rotationhi Stefy, You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei #6 20121201 22:31:20
Re: Question about rotationWell, it depends on which line you are rotating around first... The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment 