\"\"

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(a)

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The triangle side is \"\" and angle is \"\"

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The laws of sines : \"\"

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The angle \"\" is acute angle,

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Recall the relation from the ambiguous case: \"\".

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If triangle has one solution and  \"\" is an acute angle , then \"\" and \"\".

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\"\" and \"\".

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Substitute \"\", \"\" in \"\".

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\"\"

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\"\"

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If triangle has one solution, then values of  \"\" are  \"\" and \"\".

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\"\"

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(b)

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If triangle has two solutions and \"\" is an acute angle , then \"\".

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Substitute the corresponding value in above formula.

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\"\".

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Divide each side by \"\".

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\"\"

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\"\"

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\"\"

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Finally conclude that  \"\".\"\"

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(c)

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If triangle has no solution and \"\" is an acute angle, then \"\".

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\"\"

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Divide each side by \"\".

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\"\"

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

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\"\".

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\"\"

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(a) \"\" and \"\".

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(b) \"\".

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(c) \"\".