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In DeltaABC , AB =AC , BE and CF are th...

In `DeltaABC` , AB =AC , BE and CF are the bisectors of the angles `angleABCandangleACB` and they intersect AC and AB at the points E and F respectively. Then four points B ,C ,E , F are not concyclic.

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since in `DeltaABC` AB= AC ,
`thereforeangleABC=angleACBrArr(1)/(2)angleABC=(1)/(2)angleACB`
`rArrangleCBE=angleBCF[because`BE and CF are the bisector of `angleABCandangleACB` respectively]
`rArrangleBEC=angleBFC[becauseangleABC=angleACB]`
Thus , the angles , `angleBECandangleBFC` on the same side of BC are equal , so but given that B ,C , E , F are not concyclic. (by theorem-36).
But given that B, C , E , F are not concyclic.
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