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Problem
Problem
If
n
C
r
=
n
C
r
−
1
{}^nC_r = {}^nC_{r-1}
n
C
r
=
n
C
r
−
1
and
n
C
r
=
n
+
1
C
r
{}^nC_r = {}^{n+1}C_r
n
C
r
=
n
+
1
C
r
, the value of
n
n
n
is a. 2 b. 3 c. 4 d. 5
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