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Thread: Anyone Know Calculus? I Need Help

  1. #1
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    Anyone Know Calculus? I Need Help

    I need help finding the derivative of (2+x-x^2)/(x+1)^2

    I'm using the quotient rule and ****ing it up... Anyone know how to do it?

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    Hopefully this will help.

    http://www.karlscalculus.org/divrules.html

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    Check the following out.. I tried to break things down as much as I could, as I understand that calculus tends to be a complete culture shock for some of us.

    We have this:

    (2+x-x^2)/(x+1)^2

    --First, reduce the expression by canceling out the common factor terms (x+1) from both numerator and denominator.

    ex: -((x+1)(x-2)) / (x+1)(x+1)

    --Then, after reducing the above equation, you find the derivative of the expression:

    d/dx = -(x-2)/(x+1)

    --*As you correctly stated, using the quotient rule, that yields:

    d/dx = -(x+1)(x-2)/(x+1)^2

    --Simplyfing it a bit further, you get:

    d/dx = -(x-2)/(x+1) = 1/((x+1)(x-2)/((x+1)^2)

    --Multiplying by the reciprocal:

    (1/-(x+1)(x-2))(1/((x+1)^2)

    --Finally, you combine common factors (x+1) by exponential sums:

    [-1/(x+1)^3(x-2)]

    Let me know if you have questions about this.

    Max
    Last edited by "Maximus"; 04-26-2011 at 06:34 PM.

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    Thanks for you help, man. I'm gonna look things over and see if I can get it now. I'll most likely be back... this shit is whack.

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  7. #7
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    it's been 30 years... sorry!

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    If it wasn't for the "bell" curve used back when I was in university....would have NEVER passed!

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    gotta love those curves!

    I mean bell curves.... you knew that's what I meant, right?

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    Quote Originally Posted by Times Roman View Post
    it's been 30 years... sorry!
    you probably used an abacus!

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    Quote Originally Posted by 00ragincajun00 View Post
    you probably used an abacus!
    Actually, by using one was how I learned to carry out basic arithmetic operation in elementary school..

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    No need for fancy calculators, until I got to university.. And there's no such thing as division by zero! It simply does not exist; nor is possible..

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    Quote Originally Posted by JDawg1536 View Post
    Thanks for you help, man. I'm gonna look things over and see if I can get it now. I'll most likely be back... this shit is whack.
    No problem man.. Just let me know if you need more help or clarification on this.. I noticed that I omitted a negative sign on the step below. I wish I could've shown you the hand written solution.

    --Simplyfing it a bit further, you get:

    d/dx = -(x-2)/(x+1) = 1/-((x+1)(x-2)/(x+1)^2))

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    Quote Originally Posted by 00ragincajun00 View Post
    you probably used an abacus!
    LMAO! Sorry Times...that is funny as hell!!!

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    I had to take up to calc2 in college. That's when i lost most of my hair.

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    lo d hi - hi d low denominator squared we go!

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