If `sin(B+C-A),sin(C+A-B),sin(A+B-C),` are `AdotPdot,t h e ncot A ,cot B ,cot Ca r ein` `G P` (b) `H P` (c) `A P` (d) none of these

Explanation

Given:

`sin(B+C−A),sin(C+A−B),sin(A+B−C)` are in A.P

So,
`b-a=c-a`

Thus,

`=>sin(C+A−B)−sin(B+C−A)=sin(A+B−C)−sin(C+A−B)`

Using formula `sinA-sinB=2sin(A+B)/2cos(A-B)/2`

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