Step 1 :

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The equation of the curve is $\"\"$ .

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Graph:

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Graph the curve.

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$\"\"$

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Rotation formula :

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If the x and y-axes are rotated through an angle $\"\"$ , the coordinates $\"\"$ of a point P relative to the xy-plane and the coordinates $\"\"$ of the same point relative to the new x and y-axis and are related by the formulas $\"\"$ and $\"\"$ .

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The general form is $\"\"$

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The angle is $\"\"$

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If $\"\"$ , then $\"\"$ , so $\"\"$ .

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If $\"\"$ , then $\"\"$ , so $\"\"$ .

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Step 2 :

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The equation of the curve is $\"\"$ .

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Compare $\"\"$ with $\"\"$

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$\"\"$ and $\"\"$ .

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Substitute $\"\"$ and $\"\"$ in $\"\"$

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$\"\"$

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$\"\"$

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The rotation angle is $\"\"$ .

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