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    I'm not sure if what I've done so far is correct but I can't figure what to do next.

    Each edge of a contracting cube is decreasing at a rate of 0.06cms^-1.
    Find rate of decrease of the volume.

    Here's what Ive done:
    dv/dt = dx/dt x dv/dx

    v = x^3
    dv/dx = 3x^2
    Sub in

    dv/dt = 0.06 x 3x^2
    dv/dt = 0.18x^2

    Here is where I get stuck, I tried to find value for x but am not getting correct answer.
    Thanks for any help.
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    You said both v and x are functions of time to you'd want v on the RHS of your last equation. I haven't done this in a long time, but i presume you have \dfrac{dv}{dt}=f(v(t)) where f(v(t))=\sqrt[3]{v} and solve as usual. substitute x back in afterwards because you know the relationship
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    Ok, thanks for your help.
 
 
 
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Updated: February 11, 2010
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