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    also last minute i cant figure out what to do
    ok for part a) they said to prove that the tangent to the rectangular hyperbola with equation xy=c^2 (c>0) at the point (ct, c/t)
    is this : t^2(y) + x = 2ct

    i done that part
    b)then the y say tangents are drawn from the point (-3,3) to the rectangular hyperbola with equation xy=16.
    find the coordinates of the points of contact of these tangents with the hyperbola.

    any help with b? please exam in an hr and a half!
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    (Original post by kriztinae)
    also last minute i cant figure out what to do
    ok for part a) they said to prove that the tangent to the rectangular hyperbola with equation xy=c^2 (c>0) at the point (ct, c/t)
    is this : t^2(y) + x = 2ct

    i done that part
    b)then the y say tangents are drawn from the point (-3,3) to the rectangular hyperbola with equation xy=16.
    find the coordinates of the points of contact of these tangents with the hyperbola.

    any help with b? please exam in an hr and a half!
    xy = 16
    c = ±4

    substitute into t^2(y) + x = 2ct

    for your eqns of tangents

    t²y + x = ±8t

    the point (-3,3) satisfies this eqn - so substitute x=-3, y=3 and solve for t.
    Hence the tangent pts (ct, c/t)
    • Thread Starter
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    (Original post by Fermat)
    xy = 16
    c = ±4

    substitute into t^2(y) + x = 2ct

    for your eqns of tangents

    t²y + x = ±8t

    the point (-3,3) satisfies this eqn - so substitute x=-3, y=3 and solve for t.
    Hence the tangent pts (ct, c/t)
    thanx but i just did my exam and it didnt come up thankfull! no more p5! forever!!!!!
 
 
 
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