Chord of contact of pair of tangents drawn from , each point on the line
2x+y=4 , to the parabola y2=4x pass through which fixed point??
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5 Answers
1the equation of chord of contact to a parabola from a point x1,y1 is
yy_1-2(x+x_1)=0
now we make a constraint relationship on x_1 \ and \ y_1
i.e
y1=4-2x1
y(2-x_1)-x-x_1=0\\ 2y-x-x_1(y+1)\\
so the answer is
(-2,-1)
1hey can u plzz temme how u solved the eq.n 2y-x-x1(y+1)=0.i reached here but wasn't able to proceed[2][2][2][2]
1its repesenting the family of lines passing thru the intersection of lines
2y-x=0
and
y=-1
its of form
L1+λL2=0
where λ is a parameter
here x1 is parameter
