Determine the points on the curve `x^2=4y` which are nearest to the point `(0,\ 5)` .

Explanation

`x^2=4y`

`D=sqrt{(x-0)^2+(y-5)^2}`

`D^2=4y+(y-5)^2`

Now,

`{dD^2}/{dy}=4+2(y-5)`

Put `{dD^2}/{dy}=0`

`implies 4+2(y-5)=0`

`implies y=3`

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