Results 1 to 4 of 4

Math Help - Cost of producing X units.....

  1. #1
    Junior Member xterminal01's Avatar
    Joined
    Nov 2007
    Posts
    52

    Cost of producing X units.....

    A manufacturer finds that the cost of producing x units weekly is
    C(x)=3000-55x+4x^2 dollars

    If the production level is increasing steadily at the rate of 5 units per week. how fast are production cost changing when the production level reaches 8 units per week.
    So i first took the derivative but am stuck of what to do next?
    dc/dt = -55dx/dt + 8dx/dt
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member malaygoel's Avatar
    Joined
    May 2006
    From
    India
    Posts
    648
    Quote Originally Posted by xterminal01 View Post
    A manufacturer finds that the cost of producing x units weekly is
    C(x)=3000-55x+4x^2 dollars

    If the production level is increasing steadily at the rate of 5 units per week. how fast are production cost changing when the production level reaches 8 units per week.
    So i first took the derivative but am stuck of what to do next?
    dc/dt = -55dx/dt + 8dx/dt
    you have differentiated wrong
    dc/dt = -55dx/dt + 8xdx/dt
    you have dx/dt=5
    and x=8units per week...hence you can find dc/dt.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member xterminal01's Avatar
    Joined
    Nov 2007
    Posts
    52
    ?
    Quote Originally Posted by malaygoel View Post
    you have differentiated wrong
    dc/dt = -55dx/dt + 8xdx/dt
    you have dx/dt=5
    and x=8units per week...hence you can find dc/dt.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Super Member malaygoel's Avatar
    Joined
    May 2006
    From
    India
    Posts
    648
    Quote Originally Posted by xterminal01 View Post
    A manufacturer finds that the cost of producing x units weekly is
    C(x)=3000-55x+4x^2 dollars

    If the production level is increasing steadily at the rate of 5 units per week. how fast are production cost changing when the production level reaches 8 units per week.
    So i first took the derivative but am stuck of what to do next?
    dc/dt = -55dx/dt + 8dx/dt
    You want to find :how fast is the production cost changing...i.e. \frac{dc}{dt}

    dc/dt = -55\frac{dx}{dt} + 8x\frac{dx}{dt}

    plugging in the values:
    dc/dt = -55(5) + 8(8)(5)

    dc/dt = 45
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. need an integer producing function
    Posted in the Algebra Forum
    Replies: 5
    Last Post: November 19th 2010, 02:13 AM
  2. Replies: 4
    Last Post: May 15th 2009, 03:37 AM
  3. Replies: 0
    Last Post: April 26th 2009, 05:02 AM
  4. Replies: 3
    Last Post: November 15th 2008, 04:18 AM
  5. help producing eigenvlaues
    Posted in the Advanced Algebra Forum
    Replies: 3
    Last Post: October 14th 2008, 06:09 AM

Search Tags


/mathhelpforum @mathhelpforum