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MathsMediumMCQ2020 · 09 Jan Shift 2

Q57.If one end of a focal chord AB of the parabola y2 = 8x is at A( 12 , −2), then the equation of the tangent to it at B is: (1) 2x + y −24 = 0 (2) x −2y + 8 = 0 (3) x + 2y + 8 = 0 (4) 2x −y −24 = 0

What This Question Tests

This problem requires using the properties of a focal chord of a parabola to find the coordinates of the other endpoint and then determine the equation of the tangent at that point.

Concepts Tested

Properties of parabola focal chordEquation of tangent to parabolaCoordinates of endpoints of focal chord

Formulas Used

Equation of parabola y^2 = 4ax

Equation of tangent at (x1, y1): yy1 = 2a(x + x1)

Parametric form of parabola (at^2, 2at)

📚 NCERT Sections This Tests

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