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-Exponential and Logarithmic functions- Write an exponential function of the form...

-Exponential and Logarithmic functions- Write an exponential function of the form-example-1
User Sushan
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1 Answer

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20 votes

We are asked to write an exponential function of the form


y=ab^x

The function passes through the following two points

(3, 2) and (6, 16)

Let us substitute these two points into the above equation.

For point (3, 2):


\begin{gathered} 2=ab^3 \\ a=(2)/(b^3) \end{gathered}

For point (6, 16):


\begin{gathered} 16=ab^6 \\ a=(16)/(b^6) \end{gathered}

Equate the two equations to solve for b


\begin{gathered} (2)/(b^3)=(16)/(b^6) \\ 2\cdot b^6=16\cdot b^3 \\ (2b^6)/(2b^3)=(16b^3)/(2b^3) \\ b^3=8 \\ b=\sqrt[3]{8} \\ b=2 \end{gathered}

So, the value of b is 2

Finally, the value of a is given by


a=(2)/(b^3)=(2)/((2)^3)=(2)/(8)=(1)/(4)

So, the value of a is 1/4

Therefore, the exponential function is


y=(1)/(4)\cdot2^x

User AndreasM
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