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    got these just want to make suree I've answered them correctly
    everybody feel free to help:p:
    A-*find the limit if it exist
    1)lim(x-->2) [√(x+2) - √(2x)]/ [x²-2x]

    2)lim(x--> *negative infinity*) [√(5x²-2)]/(x+3)]

    3)lim (x-->3 from the left) [ lx-3l/(x-3)²]

    B-eliminatet to find a cartesian equation of the curve, sketch the curve . indicate with an arrow the dircetion in which the curve is traed as t increases

    x=cos²t y=cost 0 <=t<=(π/2)
    this on I've got a y=√x but i'm not sure, the direction was downwords, and it was reall shrt with coordinates or (1,1) and (0,0)

    D-find the domain of
    √(X+3)/(lxl+x)

    solve for x
    [lx²-16l/(x²-x-6)]<=0


    I solved all of them but I dont have the key answer, I just wat to make sure I've answered them correctly
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    A 1) -1/8
    2) -5
    3) -infinity

    B) t increases -> cost decrease -> x decrease -> arrow from right to left.

    D) Domain: x > 0
    x = +/-4
    or -2 < x < 3
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    (Original post by BCHL85)


    [/B]2) -5 are you sure not -sqrt 5???

    3) -infinity
    in the end I reached (-1/0) but then I though if it was coming from left then it's 0 from left then I thought if -1/0from left, then minuses cancel and it become +infinity


    B) t increases -> cost decrease -> x decrease -> arrow from right to left. yeah and did the caretisian sketch look like y=√x ???,I mean can we subtitute cos²t=x with cos t =√x???

    D) Domain: x > 0
    x = +/-4
    or -2 < x < 3
    I wrote x*E (-4,4) - {-2,3} can we do this?
    thanx alot by the way
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    yup, I meant to type -rt(5). Sorry
    y = rt(x) is right, as cost > 0 for 0 < t < pi/2

    You should write x E {-4, 4} U (-2, 3)
    as {} for a set of elements, while () for the range , U for union
 
 
 

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