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Sauda,c~oes, Um pequeno aquecimento, tirado de uma
outra
lista.
> Another problem from the Greek pariodical
_Euclid_ (Sept. 1971, p. 8).
> > Let ABC be a triangle. The vertices B, C move [on the sides of the >angle A] so that: (AB)^(-1) + (AC)^(-1) = k^(-1), > where k is fixed length.
> Which is the locus of the foot A' of the altitude AA'? Fortunately, this one is quite easy. .
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If P is the common point of BC and the A-bisector, AP = 2 k cos(A/2), thus P is a fixed point and A' lies on the circle with diameter AP. Friendly. Jean-Pierre []'s
Luís
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