Product with reciprocal term binomial

One binomial contains a reciprocal term (like 1/x or 1/(2x)) which must be expanded first, then multiplied by another binomial to find a coefficient.

14 questions

CAIE P1 2021 November Q1
1
  1. Expand \(\left( 1 - \frac { 1 } { 2 x } \right) ^ { 2 }\).
  2. Find the first four terms in the expansion, in ascending powers of \(x\), of \(( 1 + 2 x ) ^ { 6 }\).
  3. Hence find the coefficient of \(x\) in the expansion of \(\left( 1 - \frac { 1 } { 2 x } \right) ^ { 2 } ( 1 + 2 x ) ^ { 6 }\).
CAIE P1 2010 June Q2
2
  1. Find the first 3 terms in the expansion of \(\left( 2 x - \frac { 3 } { x } \right) ^ { 5 }\) in descending powers of \(x\).
  2. Hence find the coefficient of \(x\) in the expansion of \(\left( 1 + \frac { 2 } { x ^ { 2 } } \right) \left( 2 x - \frac { 3 } { x } \right) ^ { 5 }\).
CAIE P1 2010 June Q2
2
  1. Find the first three terms, in descending powers of \(x\), in the expansion of \(\left( x - \frac { 2 } { x } \right) ^ { 6 }\).
  2. Find the coefficient of \(x ^ { 4 }\) in the expansion of \(\left( 1 + x ^ { 2 } \right) \left( x - \frac { 2 } { x } \right) ^ { 6 }\).
CAIE P1 2013 June Q2
2 Find the coefficient of \(x ^ { 2 }\) in the expansion of
  1. \(\left( 2 x - \frac { 1 } { 2 x } \right) ^ { 6 }\),
  2. \(\left( 1 + x ^ { 2 } \right) \left( 2 x - \frac { 1 } { 2 x } \right) ^ { 6 }\).
CAIE P1 2014 June Q2
2 Find the coefficient of \(x ^ { 2 }\) in the expansion of \(\left( 1 + x ^ { 2 } \right) \left( \frac { x } { 2 } - \frac { 4 } { x } \right) ^ { 6 }\).
CAIE P1 2017 June Q1
1
  1. Find the coefficient of \(x\) in the expansion of \(\left( 2 x - \frac { 1 } { x } \right) ^ { 5 }\).
  2. Hence find the coefficient of \(x\) in the expansion of \(\left( 1 + 3 x ^ { 2 } \right) \left( 2 x - \frac { 1 } { x } \right) ^ { 5 }\).
CAIE P1 2019 June Q2
2
  1. In the binomial expansion of \(\left( 2 x - \frac { 1 } { 2 x } \right) ^ { 5 }\), the first three terms are \(32 x ^ { 5 } - 40 x ^ { 3 } + 20 x\). Find the remaining three terms of the expansion.
  2. Hence find the coefficient of \(x\) in the expansion of \(\left( 1 + 4 x ^ { 2 } \right) \left( 2 x - \frac { 1 } { 2 x } \right) ^ { 5 }\).
    \includegraphics[max width=\textwidth, alt={}, center]{f462c036-45d3-4679-ad53-4edbf99df76d-04_385_655_262_744} The diagram shows triangle \(A B C\) which is right-angled at \(A\). Angle \(A B C = \frac { 1 } { 5 } \pi\) radians and \(A C = 8 \mathrm {~cm}\). The points \(D\) and \(E\) lie on \(B C\) and \(B A\) respectively. The sector \(A D E\) is part of circle with centre \(A\) and is such that \(B D C\) is the tangent to the \(\operatorname { arc } D E\) at \(D\).
  3. Find the length of \(A D\).
  4. Find the area of the shaded region.
Edexcel C12 2019 June Q6
6. (a) Find, in ascending powers of \(x\), up to and including the term in \(x ^ { 3 }\), the binomial expansion of $$\left( 1 + \frac { 1 } { 4 } x \right) ^ { 12 }$$ giving each term in its simplest form.
(b) Hence find the coefficient of \(x\) in the expansion of $$\left( 3 + \frac { 2 } { x } \right) ^ { 2 } \left( 1 + \frac { 1 } { 4 } x \right) ^ { 12 }$$
Edexcel P2 2019 October Q3
3. (a) Find the first 4 terms, in ascending powers of \(x\), in the binomial expansion of $$\left( 1 + \frac { x } { 4 } \right) ^ { 12 }$$ giving each coefficient in its simplest form.
(b) Find the term independent of \(x\) in the expansion of $$\left( \frac { x ^ { 2 } + 8 } { x ^ { 5 } } \right) \left( 1 + \frac { x } { 4 } \right) ^ { 12 }$$
Edexcel P2 2020 October Q1
  1. (a) Find the first 4 terms, in ascending powers of \(x\), of the binomial expansion of
$$\left( 2 - \frac { x } { 4 } \right) ^ { 10 }$$ giving each term in its simplest form.
(b) Hence find the constant term in the series expansion of $$\left( 3 - \frac { 1 } { x } \right) ^ { 2 } \left( 2 - \frac { x } { 4 } \right) ^ { 10 }$$
Edexcel AS Paper 1 2022 June Q6
  1. (a) Find the first 4 terms, in ascending powers of \(x\), of the binomial expansion of
$$\left( 3 - \frac { 2 x } { 9 } \right) ^ { 8 }$$ giving each term in simplest form. $$f ( x ) = \left( \frac { x - 1 } { 2 x } \right) \left( 3 - \frac { 2 x } { 9 } \right) ^ { 8 }$$ (b) Find the coefficient of \(x ^ { 2 }\) in the series expansion of \(\mathrm { f } ( x )\), giving your answer as a simplified fraction.
Edexcel AS Paper 1 2023 June Q14
  1. Find, in simplest form, the coefficient of \(x ^ { 5 }\) in the expansion of
$$\left( 5 + 8 x ^ { 2 } \right) \left( 3 - \frac { 1 } { 2 } x \right) ^ { 6 }$$
AQA C2 2013 January Q8
8
  1. Expand \(\left( 1 + \frac { 4 } { x } \right) ^ { 2 }\).
  2. The first four terms of the binomial expansion of \(\left( 1 + \frac { x } { 4 } \right) ^ { 8 }\) in ascending powers of \(x\) are \(1 + a x + b x ^ { 2 } + c x ^ { 3 }\). Find the values of the constants \(a , b\) and \(c\).
  3. Hence find the coefficient of \(x\) in the expansion of \(\left( 1 + \frac { 4 } { x } \right) ^ { 2 } \left( 1 + \frac { x } { 4 } \right) ^ { 8 }\).
SPS SPS SM Pure 2023 September Q1
1. a) Find the first four terms, in ascending powers of \(x\), of the binomial expansion of \(\left( 1 + \frac { x } { 2 } \right) ^ { 7 }\), giving each coefficient in exact simplified form.
b) Hence determine the coefficient of \(x\) in the expansion of $$\left( 1 + \frac { 2 } { x } \right) ^ { 2 } \left( 1 + \frac { x } { 2 } \right) ^ { 7 }$$ [BLANK PAGE]