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From the point (-1,2), tangent lines are to the parabola y^(2)=4x. If the area of the triangle formed by the chord of contact and the tangents is A, then the value of A//sqrt(2) is ___________ .

Answer» <html><body><p><br/></p>Solution :(8) The chord of contact w.r.t point O(-1,2) is <br/> `y=(x-1)"[Using "yy_(1)=2a(x+x_(1))]` <br/> Solving y=x-1 with the parabola, we get the point of intersection as <br/> `P(3+2sqrt(2),2+2sqrt(2))andQ(3-2sqrt(2),2-2sqrt(2))` <br/> `:." "<a href="https://interviewquestions.tuteehub.com/tag/pq-592546" style="font-weight:bold;" target="_blank" title="Click to know more about PQ">PQ</a>^(2)=32+32=64` <br/> `:." "PQ=8`<br/> <a href="https://interviewquestions.tuteehub.com/tag/also-373387" style="font-weight:bold;" target="_blank" title="Click to know more about ALSO">ALSO</a>, the length of perpendicular from O(-1,2) on PQ is `4//sqrt(2)`. <br/> Then the required <a href="https://interviewquestions.tuteehub.com/tag/area-13372" style="font-weight:bold;" target="_blank" title="Click to know more about AREA">AREA</a> of triangle is <br/> `A=(1)/(2)xx8xx((4)/(sqrt(2)))=8sqrt(2)` sq. units</body></html>


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