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Determining Exponential Growth and Decay in Exercise, use the given information to write an exponential equation for y. Does the function represent exponential growth or exponential decay?
dy/dt = 2y, y = 10 when t = 0

Respuesta :

Answer:

[tex]y=10e^{2t}[/tex]

Growth function

Step-by-step explanation:

We are given that

[tex]\frac{dy}{dt}=2y[/tex]

y=10 when t=0

Taking integration on both sides then we get

[tex]\int \frac{dy}{y}=\int 2dt[/tex]

[tex]lny=2dt+C[/tex]

Using formula

[tex]\int\frac{dx}{x}=lnx,\int dx=x[/tex]

[tex]y=e^{2t+C}[/tex]

[tex]y=e^C\cdot e^{2t}=Ce^{2t}[/tex]

[tex]ln x=y\implies x=e^y[/tex]

[tex]e^C=Constant=C[/tex]

Substitute y=10 and t=0

[tex]10=C[/tex]

Substitute the value of C

[tex]y=10e^{2t}[/tex]

When t tends to infinity then

[tex]\lim_{t\rightarrow \infty}=\lim_{t\rightarrow\infty}10e^{2t}=\infty[/tex]

Hence, the exponential function is growth function.