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ΔABC has three sides with these lengths: AB = 9, BC = 40, and CA = 41. What is the value of cos C?

User Jetti
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2 Answers

2 votes

Answer:

c=40/41

Explanation:

corect for plato

User Vladievlad
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From the Law of Cosines
Cos (C) = (a^2 + b^2 -c^2) / 2 * a * b
Cos (C) =(40^2 + 41^2 -9^2) / 2 * 40 * 41
Cos (C) = 1,600 + 1,681 - 81 / 3,280
Cos (C) = 3,200 / 3,280
Cos (C) = 0.9756097561
Incidentally, Angle C = 12.68 Degrees


ΔABC has three sides with these lengths: AB = 9, BC = 40, and CA = 41. What is the-example-1
User Arjun T Raj
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