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FIND THE FORMULA FOR THE EXPONENTIAL GRAPHThe figure shows the graph of an exponential function. The dots on the graph are points with integer coordinates.The function graphed is P(t)Hint: The function may be written as P(t) = Pa^t

FIND THE FORMULA FOR THE EXPONENTIAL GRAPHThe figure shows the graph of an exponential-example-1
User LDK
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1 Answer

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Based on the graph,

At,

f(2) = 1 (1)

f(9) = 6 (2)


\text{ f(x) = ab}^{\text{x}}

At f(2) = 1,


\text{ 1 = ab}^2
\text{ a = }\frac{\text{ 1}}{b^2}

At f(9) = 6 ,


\text{ 6 = ab}^9
\text{ a = }\frac{\text{ 6}}{b^9}

Equate them to find b, a = a,


\text{ }\frac{\text{ 1}}{b^2}\text{ = }\frac{\text{ 6}}{b^9}\text{ }\rightarrow\text{ }(b^9)/(b^2)\text{ = }(6)/(1)
\text{ b}^7\text{ = 6}
\text{ b = }\sqrt[7]{6}

Let's find a at f(2) = 1 and the seventh root of 6,


\text{ f(x) = ab}^{\text{x}}
\text{ 1 = a(}\sqrt[7]{6})^2
\text{ a = }\frac{\text{ 1}}{\sqrt[7]{36}}

Let's now complete the equation.


\text{ f(x) = ab}^{\text{x}}


\text{ f(x) =}\frac{1}{\sqrt[7]{36}}\text{ x (}\sqrt[7]{6})^x=\frac{\text{(}\sqrt[7]{6})^x}{\sqrt[7]{36}}
\text{ f(x) }=\frac{\text{(}\sqrt[7]{6})^x}{\sqrt[7]{36}}

User David Carlisle
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