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    Hey im struggling with this question on further rational functions and max and min points.

    Q: A curve has equation y = x^2-6 / x^2+4x+5

    a) prove that the curve only exists for -3< or equal to y< or equal to 2

    b) Hence determine the co-ordinates of stationary points of the curve.

    Ive tried a)

    I multiplied y by x^2+4x+5 which gives yx^2+4xy+5y - x^2+6 = 0

    then i tried to factor out the y's : (y-1)x^2 + y(4x+5) +6=0

    Then I would assume you would do b^2-4ac >(greather than or equal to) 0

    But by now I've made an error some where as that doesnt work (or maybe im doing it wrong lol).

    Please help.
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    (Original post by marek35)
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    You have the right idea but you lost the plot when forming your quadratic.

    You should have obtained:

    (y-1)x^2 + (4y)x + (5y+6) = 0
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    (Original post by Mr M)
    You have the right idea but you lost the plot when forming your quadratic.

    You should have obtained:

    (y-1)x^2 + (4y)x + (5y+6) = 0
    lol Im guessing I messed up whereby a quadratic is in the form ax^2 +bx+c

    Makes sense.

    Cheers!

    EDIT: This is the problem ive been having all along.. getting them right now thanks Mr M!
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    (Original post by marek35)
    lol Im guessing I messed up whereby a quadratic is in the form ax^2 +bx+c

    Makes sense.

    Cheers!

    EDIT: This is the problem ive been having all along.. getting them right now thanks Mr M!
    Good stuff.
 
 
 
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Updated: March 25, 2011
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