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Problems
Contests
National and Regional Contests
Turkey Contests
National Olympiad First Round
1999 National Olympiad First Round
33
33
Part of
1999 National Olympiad First Round
Problems
(1)
Turkish NMO First Round - 1999 P-33 (Geometry)
Source:
7/3/2012
\left|AC\right| \equal{} 8 \sqrt {2},
B
B
B
is the midpoint of
[
A
C
]
\left[AC\right]
[
A
C
]
,
E
E
E
is the midpoint of arc
A
B
AB
A
B
of a circle having chord
[
A
B
]
\left[AB\right]
[
A
B
]
, and
D
D
D
is the point of tangency drawing from
C
C
C
.(
D
D
D
lies on the opposite side of line
A
B
AB
A
B
to
E
E
E
). If \left[DE\right]\bigcap \left[AB\right] \equal{} \left\{F\right\}, \left|CF\right| \equal{} ?
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3
<span class='latex-bold'>(A)</span>\ 5\sqrt {2} \qquad<span class='latex-bold'>(B)</span>\ 4\sqrt {2} \qquad<span class='latex-bold'>(C)</span>\ 8 \qquad<span class='latex-bold'>(D)</span>\ 6 \qquad<span class='latex-bold'>(E)</span>\ 4\sqrt {3}
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3
geometry