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Identify the parabola touched by every line in a family

The line y=mx+3/my=mx+3/m is tangent to the parabola y2=kxy^2=kx for every m≠0m\ne0. Find kk and the coordinates of contact in terms of mm. marks

[2014/VJC/I/1]

CJC · Review problems · Question 7

A tangent contact produces equal gradients or a repeated intersection root.

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