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  - Trigonometric Ratios of Obtuse Angles
  - Ambiguous Case of the Sine Law
  - Solving Oblique Triangles
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Oblique Triangles

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In this lesson, we will extend our usage of the sine, cosine, and tangent ratios to handle obtuse angles. This will require us to take extra care to deal with ambiguities that can arise when working with the sine ratio.

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Lesson Goals

Compute the sine, cosine, and tangent ratios for obtuse angles.
Determine the oblique angle or angles corresponding to a given trigonometric ratio.
Solve an oblique triangle using the sine and cosine laws and correctly handle the ambiguous case of the sine law when encountered.

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In \(\triangle ABC\), determine obtuse \(\angle B\) to the nearest degree.

Triangle ABC with side AC equal to 8, side BC equal to 6, and angle A equal to 40 degrees.

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Oblique Triangles

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Lesson Goals

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