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The number of microbes in a tissue sample is given by the functionN (t) = 34.8 + In(1 + 1.2t)where N(t) is the number of microbes (in thousands) in the sample after thours.a.) How many microbes are present initially?b.) How fast are the microbes increasing after 10 hours?

User Pauli Nieminen
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1 Answer

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Step-by-step explanation


N(t)=34.8+\ln (1+1.2t)

we have a function where the number of microbes ( N) depends on the time(t)

hence

Step 1

a.) How many microbes are present initially?

to know this, we need replace time I= t = zero, because it was "initially"

so

when t=0

replace.


\begin{gathered} N(t)=34.8+\ln (1+1.2t) \\ N(0)=34.8+\ln (1+1.2\cdot0) \\ N(0)=34.8+\ln (1) \\ N(0)=34.8+0 \\ N(0)=34.8 \end{gathered}

so, initially there were 34.8 microbes

Step 2

b)How fast are the microbes increasing after 10 hours?

to know this, let t=10

so


\begin{gathered} N(t)=34.8+\ln (1+1.2t) \\ N(10)=34.8+\ln (1+1.2\cdot10) \\ N(10)=34.8+\ln (1+12) \\ N(10)=34.8+\ln (13) \\ N(10)=34.8+2.56 \\ N(10)=37.36 \end{gathered}

therefore , after 10 hours the number of microbes is 37.36

I hope this helps you



User TheKobra
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