## Construction of tangents
In order to find the tangents from a point
P to a conic,
we choose two
lines through P
which intersect the conic. Then we construct the harmonic conjugates
F and _{1}F of _{2}P with respect to the two pairs G, and
_{1}H_{1}G. The line connecting _{2}H_{2}F and _{1}F is the polar to _{2}P
and intersects the conic in the contact points of the tangents through P.
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