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    the circled part.

    question asks:
    newton's law of cooling is

    dT/dt = -k(T-Ts)

    (T- temperature of cooling body, Ts- temperature of surrounding)

    By defining x=(T-Ts), determine the differential equation for x. Write down the solution of this equation.

    thanks!
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    Which line: x=Ae^{-kt} or T = T_s + Ae^{-kt}?
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    (Original post by DFranklin)
    Which line: x=Ae^{-kt} or T = T_s + Ae^{-kt}?
    both, sorry
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    Getting the 2nd line from the first is trivial - you've defined x to equal T-T_s, so T=T_s+x.

    For the first bit, do you know how to solve a separable differential equation?
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    (Original post by DFranklin)
    Getting the 2nd line from the first is trivial - you've defined x to equal T-T_s, so T=T_s+x.

    For the first bit, do you know how to solve a separable differential equation?
    ah great thanks

    no i don't understand how to solve a sep. diff. equation. it seems to be my problem for every question like this, i should get that sorted!
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    http://www.sosmath.com/diffeq/first/...separable.html
 
 
 
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