\"\"

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Baseball diamond with a square side \"\" ft.

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Batter hits the ball and then runs towards the first base with a speed of 24 ft/s.

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Draw diagram with the given specifications :

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\"\"

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From the figure,

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The man hits the ball at point \"\" and runs towards the point \"\".

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At any time \"\", assume that man reaches some point \"\", distance covered by him is \"\" ft .

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\"\" and \"\".

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Speed of the man \"\" ft/s.

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Assume the distance between the man and second base as \"\" at \"\" sec.

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\"\".

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Since it is a square court, we have \"\" ft.

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\"\"

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(a)

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Apply Pythagorean theorem to the \"\".

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\"\".

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Substitute \"\" \"\" and \"\" in above expression.

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\"\".

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Differentiate on each side with respect to \"\".

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\"\" 

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Here it is needed to determine at what rate is his distance from third base increasing when he is halfway to first base.

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Thus, \"\" ft.

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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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Therefore, distance from second base decreasing at a rate  \"\" ft/sec. 

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\"\"

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(b)

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Apply Pythagorean theorem to the  \"\".

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\"\".

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Substitute \"\" \"\" and \"\" in above expression.

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\"\".

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Differentiate on each side with respect to \"\".

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\"\"

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Here it is needed to determine at what rate is his distance from second base decreasing when he is halfway to first base.

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Thus, \"\" ft.

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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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Therefore, distance from third base is increasing at a rate  \"\" ft/sec. 

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\"\"

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(a) Distance from second base decreasing at a rate  \"\" ft/sec.

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(b) Distance from third base is increasing at a rate  \"\" ft/sec.