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Calculus limits help!?

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find the limit as x approaches 2: (3x^2+6x)/(x^2-4). i think i got it right but i just want to make sure im doing it correctly and check my answer. its for a summer assignment so its not fresh in my mind. if you could figure this out the help is appreciated! :)

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  1. say f(x) = (3x^2+6x)/(x^2-4)

                = [3x*(x+2)]/[(x-2)*(x+2)]

                = 3x/(x-2)

    As x approaches 2, the denominator approaches zero, the f(x) approaches infinity.

    If the question for limit at x approaches - 2 (which is my guess), then

      f(x) = 3/2 = 1.5


  2. Edit:

    The limit is undefined.

    The equation can be rewritten as [3x*(x+2)]/[(x+2)*(x-2)]

    The x+2 on the top and bottom cancel out, leaving

    3x/(x-2)

    Evaluate f(x) as x approaches 2 from the right:

    f(2.1)=(3*2.1)/.1=63

    f(2.01)=(3*2.01)/.01=603

    f(2.001)=(3*2.001)/.001=6003

    f(2.0001)=(3*2.0001)/.0001=60003

    As x approaches 2 from the right, f(x) approaches infinity.

    Evaluate f(x) as x approaches 2 from the left:

    f(1.9)=5.7/.1=57

    f(1.99)=5.97/.01=597

    f(1.999)=5.997/.001=5997

    f(1.9999)=5.9997/.0001=59997

    As x approaches 2 from the left, f(x) approaches negative infinity.

    The limit as x approaches 2 from the left and the limit as x approaches 2 from the right do not converge and therefore the limit is undefined.

    _/
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