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Byju's Answer
Standard XII
Mathematics
Combination
If nCx= nCy...
Question
If
n
C
x
=
n
C
y
, then x+y
=
Open in App
Solution
Given
n
C
x
=
n
C
y
.
.
.
.
.
.
.
.
(
1
)
We Know that
n
C
r
=
n
C
n
−
r
.
.
.
.
.
.
.
.
(
2
)
Comparing (1) and (2)
r
=
x
n
−
r
=
y
Now ,
x
+
y
=
r
+
n
−
r
=
n
⇒
x
+
y
=
n
Hence the value of
x
+
y
=
n
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0
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