Sum of cos A/a terms using the cosine rule
This type of question, asked 3 times: 20 Apr 2025 S1, 20 Apr 2025 S2, 25 Apr 2025 S1. All 3 questions below, oldest first.
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Question 1
20 Apr 2025 S1
141In a triangle ABC , with usual notations if a2cosA+bcosB+c2cosC=bca+cab then ∠A=
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Question 2
20 Apr 2025 S2
119In a triangle ABC, the sides a,b,c are such that they are the roots of the equation x3−11x2+38x−40=0 Then acosA+bcosB+ccosC=
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Question 3
25 Apr 2025 S1
140In a triangle ABC, with usual notations, a2cosA+bcosB+c2cosC=bca+cab. Then ∠A=
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