Derivatives Question - temperature as a funtion of time

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Derivatives Question -- temperature as a funtion of time

1. When a certain object is placed in an oven at 540°C, its temperature T(t) rises according to the equation T(t) = 540(1 – e–0.1t), where tis the elapsed time (in minutes). What is the temperature after 10 minutes and how quickly is it rising at this time?

My Work: Temp after t minutes is given. Just plug in t = 10 mins in the equation ie T = 540(1-1/e)
rate of change is dT/dt (at t = 10) = 54/e

I said the rate of change at t=10 is 54/e. 54/e is incorrect. not sure why I was dividing, in this question we need to show how you got the derivative to get full marks. Can someone help me with this.
 
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hi livestrong136! :smile:

(try using the X2 button just above the Reply box :wink:)

T = 540(1 – e–0.1t)

so what is dT/dt ? :smile:

(use the chain rule)
 
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