1.

Find the number of distinct normals that can be drawn from `(-2,1)`to the parabola `y^2-4x-2y-3=0`A. 1B. 2C. 3D. 0

Answer» Correct Answer - A
The equation of the parabola is
`(y-1)^(2)=4(x+1)`.
The equation of any normal to this parabola is
`y-1=m(x+1)-2m-m^(3)`
If passes through (-2, 1). Then,
`0=-m-2m-m^(3)rArrm^(3)+3m=0rArrm=0" "[becausem^(2)+3ne0]`
So, there is only one normal passing through (-2, 1).


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