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Applied Math, Quick Q

  • 21-05-2008 8:52am
    #1
    Sugar'n'spice
    Closed Accounts Posts: 18 ✭


    The volume, in litres, of a pollutant in a tank is given as a function of time in hours by
    the relation
    V(t) = 1000 + 250t – 50t2
    Find the initial volume, as well as the maximum volume reached, and show that it is a
    maximum.
    Determine the time te when the volume will become zero? Sketch a graph of the
    volume against time in the range t = 0 to t= te.

    I don't know where to start. I got the roots of the quadratic equation: 7.623 or 2.624. Any help?


Comments

  • #2
    LeixlipRed
    Closed Accounts Posts: 6,081 ✭✭✭LeixlipRed


    The initial volume is when time (t) is equal to zero. To find a maximum you'll have to do some differentiation. Don't want to help too much as this is not a difficult problem.


  • #3
    Sugar'n'spice
    Closed Accounts Posts: 18 ✭Sugar'n'spice


    So letting t=0, initial volume is equal to 1000li and differentiating once i get 100t-250. Sooo


  • #4
    Thomas_S_Hunterson
    Closed Accounts Posts: 6,151 ✭✭✭Thomas_S_Hunterson


    And surely you know how to find maxima and minima given the differential of a function...


  • #5
    Sugar'n'spice
    Closed Accounts Posts: 18 ✭Sugar'n'spice


    Surely I do, but if I diddn't...


  • #6
    Thomas_S_Hunterson
    Closed Accounts Posts: 6,151 ✭✭✭Thomas_S_Hunterson


    Let the derivative equal zero and solve for x.


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  • #7
    Sugar'n'spice
    Closed Accounts Posts: 18 ✭Sugar'n'spice


    Many thanks.


  • #8
    LeixlipRed
    Closed Accounts Posts: 6,081 ✭✭✭LeixlipRed


    Is this Applied Maths for the LC? How can you have done 2 years of Maths and Applied Maths without knowing that?


  • #9
    Sugar'n'spice
    Closed Accounts Posts: 18 ✭Sugar'n'spice


    No,no. Its a module in Uni and It's just been a while. Excuse my ignorance.:o


  • #10
    LeixlipRed
    Closed Accounts Posts: 6,081 ✭✭✭LeixlipRed


    Oh right. If it was LC then I was about to suggest you start studying for the repeat already. But if it's college stuff then no reason why you should remember.


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