$\"\"$

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The time $\"\"$ to get from one house to the other as a function of the angle $\"\"$ is $\"\"$ .

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$\"\"$

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(a)

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Find the time $\"\"$ for $\"\"$ .

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The function is $\"\"$ .

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Quotient identity : $\"\"$ .

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$\"\"$ .

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Use Pythagorean theorem to find hypotenuse.

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Pythagorean theorem : $\"\"$ .

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$\"\"$

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Trigonometric ratio : $\"\"$ .

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$\"\"$ .

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Substitute the values of $\"\"$ and $\"\"$ in $\"\"$ .

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$\"\"$

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$\"\"$ hours.

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$\"\"$

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(b)

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Sally jogs 1 mile directly to the road, then 8 miles across, the 1 mile directly to the other house.

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$\"\"$

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(c)

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The value of $\"\"$ .

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$\"\"$

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The function $\"\"$ is undefined at $\"\"$ .

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So, the angle $\"\"$ must be larger than $\"\"$ .

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$\"\"$

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(a) $\"\"$ hours.

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(b) Sally jogs 1 mile directly to the road, then 8 miles across, the 1 mile directly to the other house.

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(c) Since the function $\"\"$ is undefined at $\"\"$ , the angle $\"\"$ must be larger than $\"\"$ .