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Sine and cos rocks

Geometry Level pending

If A+B+C=180 ,then Find the value of cosA+cosB+cosC-4sin(A/2)sin(B/2)sin(C/2)=======

3 3/2 1 0 2 1/2 7/2 5/2

Excel in math and science

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It's hard to learn from lectures and videos

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by mukesh jha

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