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QuizMultiple Choice

Law of Cosines — Quiz

Question 1 • Precalculus

Which equation can be used to solve for angle cap n in the triangle?

Answer
A
6 point 2 squared is equal to 3 point 6 squared plus 4 point 3 squared plus 2 3 point 6 4 point 3 cosine cap n
B
6 point 2 squared is equal to 3 point 6 squared plus 4 point 3 squared minus 3 point 6 times 4 point 3 times cosine times cap n
C
6 point 2 squared is equal to 3 point 6 squared plus 4 point 3 squared plus 3 point 6 times 4 point 3 times cosine times cap n
D
6 point 2 squared is equal to 3 point 6 squared plus 4 point 3 squared minus 2 3 point 6 4 point 3 cosine cap n

Explanation

Use the Law of Cosines: the side opposite angle n, 6.2, satisfies c² = a² + b² − 2ab cos(n). Substituting the other sides gives 6.2² = 3.6² + 4.3² − 2(3.6)(4.3)cos(n), which is choice D.

AI-written and checked against the verified answer.

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