5
You visited us
5
times! Enjoying our articles?
Unlock Full Access!
Byju's Answer
Standard XII
Mathematics
Expansions of the Form (1+x)^(-n) and (1-x)^(-n)
If the consta...
Question
If the constant term of the binomial expansion
(
2
x
−
1
x
)
n
is
−
160
, then
n
is equal to -
A
4
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
6
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
C
8
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
10
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is
C
6
General term of
(
2
x
−
1
x
)
n
is
n
C
r
(
2
x
)
n
−
r
(
−
1
x
)
r
for constant term
n
−
r
=
r
⟹
r
=
n
2
the constant term is $^{n}C_{\dfrac{n}{2}}(2)^{\dfrac{n}{2}}(-1)^{\dfrac{n}
{2}}=-160$
⟹
n
=
6
Suggest Corrections
0
Similar questions
Q.
If the constant term in the binomial expansion of
(
x
2
−
1
x
)
n
,
n
ϵ
N
is 15 then the value of n is equal to
Q.
If the constant term in the binomial expansion of
(
x
2
−
1
x
)
n
is
15
,
then
n
=
Q.
The sum of the binomial coefficients of
[
2
x
+
1
x
]
n
is equal to
256
. The constant term in the expansion is-
Q.
If the constant term, in binomial expansion
(
2
x
r
+
1
x
2
)
10
is
180
, then
r
is equal to
Q.
If coefficients of 2, 3 and 4 terms in the binomial expansion of
(
1
+
x
)
n
are in A.P, then
n
2
−
9
n
is equal to
View More
Join BYJU'S Learning Program
Grade/Exam
1st Grade
2nd Grade
3rd Grade
4th Grade
5th Grade
6th grade
7th grade
8th Grade
9th Grade
10th Grade
11th Grade
12th Grade
Submit
Related Videos
Binomial Theorem for Any Index
MATHEMATICS
Watch in App
Explore more
Expansions of the Form (1+x)^(-n) and (1-x)^(-n)
Standard XII Mathematics
Join BYJU'S Learning Program
Grade/Exam
1st Grade
2nd Grade
3rd Grade
4th Grade
5th Grade
6th grade
7th grade
8th Grade
9th Grade
10th Grade
11th Grade
12th Grade
Submit
Solve
Textbooks
Question Papers
Install app