Question

Which of the following equations correctly represnt the law of cosines?

A. b2 = a2 + b2 – 2ab ⋅ cos(C)
B. c2 = a2 + b2 – 2ab ⋅ cos(B)
C. b2 = a2 + c2 – 2ac ⋅ cos(B)
D. a2 = b2 + c2 – 2ac ⋅ cos(A)

Answer 1

Answer:c- b2=a2+c2-2ac•cos(b)

Explanation:

Answer 2

law of cosines

c^2 = a^2+b^2-2abcosC

b^2 = a^2+c^2-2accosB

a^2 = b^2+c^2-2bccosA

Choice C