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Binomial - Topical PP

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Binomial Theorem
T
AS Level Math
(9709)
e
1
The coefficients of x2 and x3 in the expansion of 3 − 2x6 are a and b respectively. Find the value of
a
.
[4]
b
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© UCLES 2017
9709/11/M/J/17
2
2
@
A
1 5
(i) Find the coefficient of x in the expansion of 2x −
.
x
[2]
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@
A
1 5
.
(ii) Hence find the coefficient of x in the expansion of 1 + 3x2 2x −
x
[4]
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© UCLES 2017
9709/12/M/J/17
2
3
The coefficients of x and x2 in the expansion of 2 + ax7 are equal. Find the value of the non-zero
constant a.
[3]
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© UCLES 2017
9709/13/M/J/17
2
@
4
1
Find the term independent of x in the expansion of 2x − 2
4x
A9
.
[4]
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© UCLES 2017
9709/12/O/N/17
4
@
5
A6
2
(i) Find the term independent of x in the expansion of
− 3x .
x
[2]
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(ii) Find the value of a for which there is no term independent of x in the expansion of
@
A6
2
1 + ax2 − 3x .
x
[3]
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© UCLES 2017
9709/13/O/N/17
3
6
(i) Find the coefficients of x2 and x3 in the expansion of 1 − 2x7 .
[3]
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(ii) Hence find the coefficient of x3 in the expansion of 2 + 5x 1 − 2x7 .
[2]
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© UCLES 2018
9709/12/F/M/18
[Turn over
3
7
(i) Find the first three terms in the expansion, in ascending powers of x, of 1 − 2x5 .
[2]
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(ii) Given that the coefficient of x2 in the expansion of 1 + ax + 2x2 1 − 2x5 is 12, find the value of
the constant a.
[3]
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© UCLES 2018
9709/11/M/J/18
[Turn over
2
8
0
x 16
The coefficient of x2 in the expansion of 2 +
+ a + x5 is 330. Find the value of the constant a.
2
[5]
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© UCLES 2018
9709/12/M/J/18
3
9
@
A
2 5
1
Find the coefficient of in the expansion of x −
.
x
x
[3]
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© UCLES 2018
9709/13/M/J/18
[Turn over
2
10
@
A
1
2 7
Find the coefficient of 2 in the expansion of 3x + 2 .
x
3x
[4]
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© UCLES 2018
9709/12/O/N/18
2
11
@
A
1
2 7
Find the coefficient of 3 in the expansion of x −
.
x
x
[3]
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© UCLES 2018
9709/13/O/N/18
3
12
The coefficient of x3 in the expansion of 1 − px5 is −2160. Find the value of the constant p.
[3]
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© UCLES 2019
9709/12/F/M/19
[Turn over
3
13
@
A
k 6
The term independent of x in the expansion of 2x +
, where k is a constant, is 540.
x
(i) Find the value of k.
[3]
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(ii) For this value of k, find the coefficient of x2 in the expansion.
[2]
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© UCLES 2019
9709/11/M/J/19
[Turn over
2
@
14
A5
2
Find the coefficient of x in the expansion of
− 3x .
x
[3]
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© UCLES 2019
9709/12/M/J/19
3
15
@
A
1 5
(i) In the binomial expansion of 2x −
, the first three terms are 32x5 − 40x3 + 20x. Find the
2x
remaining three terms of the expansion.
[3]
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A
@
1 5
.
(ii) Hence find the coefficient of x in the expansion of 1 + 4x2 2x −
2x
[2]
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© UCLES 2019
9709/13/M/J/19
[Turn over
2
@
16
1
Find the term independent of x in the expansion of 2x + 2
4x
A6
.
[3]
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© UCLES 2019
9709/11/O/N/19
3
17
@
A
x 6
The coefficient of x in the expansion of 4 + ax 1 +
is 3. Find the value of the constant a. [4]
2
2
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© UCLES 2019
9709/12/O/N/19
[Turn over
2
18
(i) Expand 1 + y6 in ascending powers of y as far as the term in y2 .
[1]
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6
(ii) In the expansion of 1 + px − 2x2 the coefficient of x2 is 48. Find the value of the positive
constant p.
[3]
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© UCLES 2019
9709/13/O/N/19
7
19
@
A
1
a 5
The coefficient of in the expansion of 2x + 2 is 720.
x
x
(a) Find the possible values of the constant a.
[3]
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(b) Hence find the coefficient of
1
in the expansion.
x7
[2]
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© UCLES 2020
9709/12/F/M/20
[Turn over
3
20
@
A
@
A
1 5
2 8
1
The coefficient of in the expansion of kx +
+ 1−
is 74.
x
x
x
Find the value of the positive constant k.
[5]
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© UCLES 2020
9709/11/M/J/20
[Turn over
2
21
@
A
2 6
(a) Find the coefficient of x in the expansion of x −
.
x
2
[2]
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@
A
2 6
.
(b) Find the coefficient of x2 in the expansion of 2 + 3x2 x −
x
[3]
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© UCLES 2020
9709/12/M/J/20
5
22
(a) Expand 1 + a5 in ascending powers of a up to and including the term in a3 .
[1]
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(b) Hence expand 1 + x + x2 5 in ascending powers of x up to and including the term in x3 ,
simplifying your answer.
[3]
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© UCLES 2020
9709/13/M/J/20
[Turn over
6
23
0
a 16
In the expansion of 2x2 +
, the coefficients of x6 and x3 are equal.
x
(a) Find the value of the non-zero constant a.
[4]
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0
a 16
.
(b) Find the coefficient of x6 in the expansion of 1 − x3 2x2 +
x
[1]
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© UCLES 2020
9709/11/O/N/20
3
24
The coefficient of x3 in the expansion of 1 + kx 1 − 2x5 is 20.
Find the value of the constant k.
[4]
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© UCLES 2020
9709/12/O/N/20
[Turn over
3
25
(a) Find the first three terms in the expansion, in ascending powers of x, of 1 + x5 .
[1]
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(b) Find the first three terms in the expansion, in ascending powers of x, of 1 − 2x6 .
[2]
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(c) Hence find the coefficient of x2 in the expansion of 1 + x5 1 − 2x6 .
[2]
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© UCLES 2021
9709/12/F/M/21
[Turn over
4
26
(a) Find the first three terms in the expansion of 3 − 2x5 in ascending powers of x.
[3]
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(b) Hence find the coefficient of x2 in the expansion of 4 + x2 3 − 2x5 .
[3]
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© UCLES 2021
9709/11/M/J/21
5
27
@
A
10 3
1
The coefficient of x in the expansion of 4x +
is p. The coefficient of
in the expansion of
x
x
@
A5
k
2x + 2 is q.
x
Given that p = 6q, find the possible values of k.
[5]
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© UCLES 2021
9709/12/M/J/21
[Turn over
9
28
(a) Write down the first four terms of the expansion, in ascending powers of x, of a − x6 .
[2]
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@
2
(b) Given that the coefficient of x in the expansion of 1 +
ax
the possible values of the constant a.
2
A
a − x6 is −20, find in exact form
[5]
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© UCLES 2021
9709/13/M/J/21
[Turn over
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