7. If A, B and C are angles of a triangle, then thedeterminant:1 cosC – InterviewSolution

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7. If A, B and C are angles of a triangle, then thedeterminant:1 cosC cos BC 1 cos A is equal to:coscos Bcos A-113.(A) 0(C) 1(B) -1(D) of these.(N.C.E.R.T. (Exemplar)

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1

2

hence, option (A) is correct.

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