MediumLaws of sines & cosines

OpenStax, Algebra and Trigonometry 2e §10.2 Non-right Triangles: Law of Cosines · Exercise 16 · Trigonometry · Laws of sines & cosines

Non-right Triangles: Law of Cosines · Exercise 16

Use the Law of Cosines to solve for the missing angle of the oblique triangle. Round to the nearest tenth.

$a = 42, b = 19, c = 30;$ find angle $A .$

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OpenStax, Algebra and Trigonometry 2e · §10.2 Non-right Triangles: Law of Cosines · Exercise 16

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