$\"\"$

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The exponential function is $\"\"$ .

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Observe the graph:

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The graph passes through the points $\"\"$ and $\"\"$ .

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Substitute above points $\"\"$ and $\"\"$ in the function $\"\"$ to find the $\"\"$ value.

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First substitute point $\"\"$ in $\"\"$ .

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$\"\"$

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

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$\"\"$

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Solve the equations $\"\"$ and $\"\"$ .

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Multiply the equations $\"\"$ by $\"\"$ .

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$\"\"$ .

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Multiply the equations $\"\"$ by $\"\"$ .

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$\"\"$ .

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Therefore,

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$\"\"$

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Logarithmic definition: $\"\"$ .

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$\"\"$

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$\"\"$ .

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$\"\"$

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Consider $\"\"$ .

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

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$\"\"$

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

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$\"\"$

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$\"\"$ .

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$\"\"$

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$\"\"$ .