find the middle term expansion (x/y-y/x)^10
Answers
Answered by
1
Answer:
Answer
(
y
x
−
x
y
)
7
∵n=7(odd)
There will be two middle terms, i.e.,
(
2
n+1
)
th
term and (
2
n+3
)
th
term.
∵n=7
Middle term in the expansion (
y
x
−
x
y
)
7
will be 4
th
and 5
th
terms.
As we know that general term of the expansion (a+b)
n
will be-
T
r+1
=
n
C
r
a
n−r
b
r
Therefore,
4
th
term in the expansion (
y
x
−
x
y
)
7
-
T
3+1
=
7
C
3
(
y
x
)
4
(
x
y
)
3
=
7
C
3
(
y
4
x
4
)(
x
3
y
3
)=
7
C
3
y
x
5
th
term in the expansion (
y
x
−
x
y
)
7
-
T
4+1
=
7
C
4
(
y
x
)
3
(
x
y
)
4
=
7
C
4
(
y
3
x
3
)(
x
4
y
4
)=
7
C
4
x
y
Hence the middle term of the expansion (
y
x
−
x
y
)
7
are-
T
4
=
7
C
3
y
x
and T
5
=
7
C
4
x
y
Similar questions