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> Circles $S\_1$ and $S\_2$ with centres $O\_1$ and $O\_2$ intersect in points A and B. The circle, which goes through points $O\_1$, $O\_2$ and $A$, intersects the circle $S\_1$ in the point $D$ and also intersects the circle $S\_2$ in the point $E$. 
>  How can I prove that $CD = CB = CE$?
>  [![enter image description here](https://i.stack.imgur.com/ve7mw.png)](https://i.stack.imgur.com/ve7mw.png)
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