A-level · Numerical methods

The trapezium ruleExam-style questions

Estimating a definite integral by slicing the area into trapezium-topped strips: the formula (h/2)[y₀ + yₙ + 2(y₁ + … + y_(n−1))], choosing h, and deciding whether the estimate is an over- or under-estimate from the curve's shape.

28 questions · A-level level · mark scheme and worked solution on each · no sign-up to try

DifficultyAllLevel 2Level 3Level 4Level 5
  1. 1
    Use the trapezium rule with 4 strips to estimate ∫04x2+1 dx\displaystyle\int_0^4 \sqrt{x^2 + 1}\,dx, giving your answer to 3 decimal places.
    Level 2 · 3 marksTry it
  2. 2
    Use the trapezium rule with 5 ordinates to estimate ∫132x dx\displaystyle\int_1^3 2^x\,dx, giving your answer to 3 decimal places.
    Level 2 · 3 marksTry it
  3. 3
    The table below shows corresponding values of xx and yy for y=5+x4y = \sqrt{5 + x^4}

    The values of yy are given to 3 decimal places as appropriate.

    x00.40.81.21.6y2.2362.2422.3262.6603.399\begin{array}{c|ccccc} x & 0 & 0.4 & 0.8 & 1.2 & 1.6 \\ \hline y & 2.236 & 2.242 & 2.326 & 2.660 & 3.399 \end{array}
    (a) Use the trapezium rule with all the values of yy in the table to find an estimate for

    ∫01.65+x4 dx\int_0^{1.6} \sqrt{5 + x^4}\,dx

    giving your answer to 3 significant figures.

    (3 marks)
    (b) Use your answer to part (a) to find an estimate for

    ∫01.6(1+45+x4)dx\int_0^{1.6} \left(1 + 4\sqrt{5 + x^4}\right)dx

    (2 marks)
    Level 2 · 5 marksTry it