Skip to content

Course home

3.3 Sequences and series (A-level only)

3.3 Sequences and series (A-level only)

EasyMediumHard
123456789101112131415161718
Question 17

The function f f\,f is given by

f(x)=1+axf(x) = \sqrt{1 + ax}f(x)=1+ax​

where a a\,a is a non-zero constant.

In the binomial expansion of f(x)f(x)f(x), the coefficients of x x\,x and x2 x^2\,x2 are equal.

a.

Find the value of aaa.

[3]
b(i).

Using this value of aaa, state, using set notation, the values of x x\,x for which the binomial expansion is valid.

[1]
b(ii).

Using this value of aaa, write down the quadratic function that approximates f(x)f(x)f(x) when x x\,x is small.

[1]
Markscheme

3.3 Sequences and series (A-level only) Questions

  1. A Level
  2. /Maths
  3. /3.3 Sequences and series (A-level only)

200 exam-style questions on CCEA A Level Maths 3.3 Sequences and series (A-level only), covering 3.3.1 Sequences and series (A-level only), 3.3.2 Sequences and series (A-level only), 3.3.3 Sequences and series (A-level only), 3.3.4 Sequences and series (A-level only), 3.3.5 Sequences and series (A-level only), 3.3.6 Sequences and series (A-level only), 3.3.7 Sequences and series (A-level only), and 3.3.8 Sequences and series (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.

Question bank