$\"\"$

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The exponential function is $\"\"$ .

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Apply the initial conditions to find the $\"\"$ value.

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Observe the graph :

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At the point $\"\"$ :

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When $\"\"$ , $\"\"$ .

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Thus, $\"\"$ .

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The exponential function is $\"\"$ .

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Above graph passes through the point $\"\"$ .

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Substitute $\"\"$ in the function $\"\"$ .

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$\"\"$

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Logarithmic definition : $\"\"$ .

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$\"\"$

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Substitute $\"\"$ in $\"\"$ .

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$\"\"$

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$\"\"$ .

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$\"\"$

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$\"\"$ .