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New equation

  1. Oct 5, 2009 #1
    The parabola y = x2 is rotated anti-clockwise about the origin through the angle 30o. What is the new equation of the new curve (relative to the standard basis)?
  2. jcsd
  3. Oct 5, 2009 #2


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    If you have a point (x,x2) and you rotate it by 30 degrees around the origin what does it become?
  4. Oct 5, 2009 #3


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    And you can rotate a point (x,y) through an angle [itex]\theta[/itex] about the origin by the matrix multiplication
    [tex]\begin{bmatrix}cos(\theta) & -sin(\theta) \\ sin(\theta) & cos(\theta)\end{bmatrix}\begin{bmatrix}x \\ y\end{bmatrix}[/tex].
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