1.

The chords of contact of the pairs of tangents drawn from each point on the line `2x +y=4` to the parabola `y^2=-4x` pass through the pointA. `(2, -1)`B. `(1//2, 1//4)`C. `(-1//2,-1//4)`D. `(-2, 1)`

Answer» Correct Answer - D
Let P(t, -2t) be any point on 2x+y=4. The chord of contact of tangents drawn from p to `y^(2)=-4x` is
`(4-2t)y=-2(x+1)`
`or, (2x+4y)-2t(y-1)=0`
Clearly, it represents a line passing through the point of intersection of the lines 2x+4y=0 and y-1=0 i.e.(-2, 1).


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