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If A,B,C be anlges of a triangle, then p...

If A,B,C be anlges of a triangle, then prove that, `|{:(-1,cosC,cosB),(cosC,-1,cosA),(cosB,cos A,-1):}|=0`

Text Solution

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The correct Answer is:
`=-sin^2A+sin^2A[because sin (B+c)=sin A] =0 `
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