Question 1034379
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Write the equation of the conic section x² + y² = 4 after a rotation of 45° about the origin.


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(x')² - 2x'y' + (y')² = 4
(x')² + (y')² = 16
(x')² + 2x'y' + (y')² = 16
(x')² + (y')² = 4                <--- This and only this
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