$\"\"$

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The function $\"\"$ on interval $\"\"$ .

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Average value of the function $\"\"$ on $\"\"$ is defined as $\"\"$ .

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In this case $\"\"$ and $\"\"$ .

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Average value of $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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Average value is $\"\"$ .

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$\"\"$

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Equate the function to its average value.

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$\"\"$ .

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Solve the equation by using graph.

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Graph the equation $\"\"$ .

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$\"\"$

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Observe the graph: Real solution of above cubic equation is $\"\"$ .

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$\"\"$

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Average value is $\"\"$ .

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$\"\"$ .