Determinants Proof Problem

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The question pertains to Trigonometric element in Determinants. To Prove that

I tried but could not get RHS.

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$$D=\sin(C-B)+\sin(A-C)+\sin(B-A)$$

Set $C-B=2X$ etc. $X+Y+Z=0,X+Y=-Z,$

$\cos(X+Y)=\cos(-Z)=?$

$\sin(X+Y)=\sin(-Z)=?$

$$=\sin2X+\sin2Y+\sin2Z$$

$$=2\sin(X+Y)\cos(X-Y)+2\sin Z\cos Z$$

$$=-2\sin Z\cos(X-Y)+2\sin Z\cos(X+Y)$$

$$=-2\sin Z[\cos(X-Y)-\cos(X+Y)]$$

$$=-2\sin Z[2\sin X\sin Y]$$