Fisrtly, note that T and t represent different variables here.
One method for solving this is called "separation of variables". You have to get all the T terms on one side and all the t terms on the other
Strictly speaking the dT/dt is not separable like this as it represents 0/0, but it works out ok if you quickly put in integration signs.
Now integrate each side. The right hand side is easy as it is just integrate a constant with respect to t. The left hand side is a natural log.
As D is just the constant of integration you can replace it with ln(C), another constant.
Bring the two log terms together using the rules for logs and then re-write the expression with e to get the required expression.
I've left a few steps for you. Post back if you need more help.
Bob
]]>You will get that if you integrate both sides
maybe you can show me?
]]>The question then states that this means that T(t)=T1+Ce^(-kt)
I don't see how they got that...can you help please?
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