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Method B2

Here P moves anti-clockwise towards E.

At one instant, Q coincides with C: what can we say about QF and QP here?
At another instant, Q coincides with E so that PQ (or PE) becomes a tangent: we seem to have a new theorem here, about a tangent and chord through a common point. We discuss this on the PS page.

What happens when P goes beyond E? Does the original situation still apply?
Might it still be the case that QF = QP ?

On the next page we move towards a proof.