Skip to content
MathsGenie logo
Open app

Course home

  1. A Level
  2. Maths CCEA
  3. Question bank

Binomial Expansion

EasyMedium
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596
Question 75

The amplitude of a signal in a circuit, S(t)S(t)S(t), can be modeled by the function

S(t)=(2−t4)8 S(t) = \left(2 - \frac{t}{4}\right)^8 S(t)=(2−4t​)8

where t t\,t represents time in milliseconds.

a.

Find the first 4 terms, in ascending powers of ttt, of the binomial expansion of S(t)S(t)S(t), giving each term in its simplest form.

[4]
b.

A noise-cancelling filter F(t)F(t)F(t) is applied such that the resulting signal is given by the product P(t)=F(t)S(t)P(t) = F(t)S(t)P(t)=F(t)S(t). Given that

F(t)=(3+2t)2 F(t) = \left(3 + \frac{2}{t}\right)^2 F(t)=(3+t2​)2

determine the constant term in the series expansion of P(t)P(t)P(t).

[3]

Binomial Expansion Questions

  1. A Level
  2. /Maths
  3. /Binomial Expansion