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We wish to place the parabola 9x^2+16y^2+24xy+22x+46y+9=0 such that its vertex is at the origin an its focus is on the positive x-axis. We first creat...
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Let B be the focus of the parabola, and D be the intersection between a tangent whose point of contact is C and the parabola axis. The triangle BDC i...
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If we take the parabola Y=aX2 and look at the length of the horizontal chord through the focus, we find this is 1/a. Salmon calls this the parameter ...
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If CD is a chord of a parabola and E its intersection with the directrix, then BE externally bisects the angle CBD.
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Draw a tangent to a parabola and a line from the focus to that tangent. Draw another line from the tangency point to the vertex, and keep the angle be...
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We examine the locus of the intersection of the perpendicular from the focus to the tangent with the horizontal from the point of contact and find it ...
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The area of the triangle formed by 3 tangents is half the area of the triangle formed by their points of contact.
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We use the evolute.
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