Question
In ∆ABC, AB = 5cm, BC = 10cm, and AC = 13cm then find out the value of cos
In ∆ABC, AB = 5cm, BC = 10cm, and AC = 13cm then find out the value of cos
A.
From the Cosine rule, we get. BC2 = AC2 + AB2 - 2AC.AB.cos A 100=25+169-2×5×13×Cos A 130CosA=194-100=94 cos A = 94/130 =47/65More Geometry Questions
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