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The point on curve y2=4xy^2 = 4x which is nearest to the point (2,−8)(2, -8) is

Solution

✅ Correct Option: 2

Parametrise the curve as (t2,2t)(t^2, 2t).

Then D2=(t2−2)2+(2t+8)2D^2 = (t^2-2)^2 + (2t+8)^2 and ddtD2=4t3−8t+8t+32=4t3+32\frac{d}{dt}D^2 = 4t^3 - 8t + 8t + 32 = 4t^3 + 32.

Setting this to zero gives t=−2t = -2, so the nearest point is (4,−4)(4,-4).

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