WEBVTT
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Okay. We know they've given us an equation.
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And we know now that if capital T is the
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temperature of a coffee after time teeth, then we
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know using Newton's law of cooling, which is listed
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in this chapter. We know we have duty over
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TFT minus 20 and we know the integral of this
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is equivalent to and to roll of negative K.
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Did you? Which gives us cheat to the T
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minus 20. Even C E to the negative.
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Katie could remember natural log times e we end up
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lifting up the exponents. Therefore, we have capital
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. Chief Chief is 20 co c e to the
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negative. Kate. Cheap number K is your point
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. You're too and t is zero there for capital
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to use 95 see if 75 therefore capital t of
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tea, the equation would be 20 with 75 e
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to the negative 0.2 times. T, this is
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part A. Now we're moving on to part B
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of this question. We know we're gonna be using
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the average value Formula one over B minus. Eso
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won over 30 minutes. You're from A to B
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from 0 30 capital G of tea. Do you
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see? We know what our function is. We
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just figured this out in part, right? Snowy
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, canned. Hello again. I'm plugging in the
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function divide by the constant care. When we take
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the integral from 0 to 30 this is equivalent to
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76.4 degrees Celsius upon plugging in.