1.

The line `x-y=1`intersects the parabola `y^2=4x`at `A`and `B`. Normals at `Aa n dB`intersect at `Cdot`If `D`is the point at which line `C D`is normal to the parabola, then the coordinates of `D`are`(4,-4)`(b) `(4,4)``(-4,-4)`(d) none of theseA. (4,-4)B. (4,4)C. (-4,-4)D. none of these

Answer» Correct Answer - B
(2) solving the line y=x-1 and the parabola `y^(2)=4x`, we have
`(x-1)^(2)=x`
`orx^(2)-6x+1=0`
`orx=3pmsqrt(8)`
`:.y=2pmsqrt(8)`
Suppose point D is `(X_(3),y_(3))`. Then,
`y_(1)+y_(2)+y_(3)=0`
`or2+sqrt(8)+2-sqrt(8)+y_(3)=0`
`ory_(3)=-4`
Then `x_(3)=4`.
Therefore, the point is (4,4).


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