Tangent Lines to a Conic Section
Tangent Lines to a Conic Section
Suppose that is a point on the conic section . Then the tangent line to the conic section at point is
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A+Bxy+C+Dx+Ey+F=0
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(2A+B+D)x+(B+2C+E)y-A-B-C+F=0.
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