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    Can someone please help me with this question:
    (I) find the value of k for which the line 2y=x+k forms a tangent to the curve y^2=2x
    (II) hence find the coordinates of the point where the line 2y=x+k meets the curve for the value of k found in part (I)
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    (2y)^2 = 8x so (x+k)^2 = 8x this is a quadratic. Expand it, for what k does it have a single root? (discriminant considerations)
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    Okay I expanded it to get x^2+2kx+k^2=8x, where do I go from that?
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    (Original post by itskerry17)
    Okay I expanded it to get x^2+2kx+k^2=8x, where do I go from that?
    Get it =0 and consider the discriminant for a single root.
 
 
 
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