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Integration by substitutionEdexcel A-Level Maths: Flashcards

What these 12 flashcards ask

  • Integration by substitution is the reverse of which rule?
  • Steps of substitution?
  • What do you do to the limits of a definite integral when substituting?
  • Substitution for \int x\left(x^2+3\right)^4dx?
  • \int x\left(x^2+3\right)^4dx?
  • \int\frac{e^x}{1+e^x}\,dx?
  • If u=2x+1, what is dx and what is x?
  • If u=\sqrt x, what are x and dx?
  • If u=\cos x, what is du?
  • How do you integrate \sin^3x?
  • Value of \int0^{\pi/2}\sin^3x\,dx?
  • How can you check a substitution result?

Exam questions on Integration by substitution

  1. Let I=∫x(x2+3)4 dxI=\int x\left(x^2+3\right)^4\,\mathrm{d}x.
    Hence find the exact value of ∫01x(x2+3)4 dx\int_0^1x\left(x^2+3\right)^4\,\mathrm{d}x.2 marks
  2. Let N=∫0ln⁡2ex1+ex dxN=\int_0^{\ln2}\frac{e^{x}}{1+e^{x}}\,\mathrm{d}x, to be found using the substitution u=1+exu=1+e^x.
    Hence find the exact value of NN.2 marks
  3. In this question, use integration by substitution with the substitution given in each part.
    Use u=1−x2u=1-x^2 to find ∫x1−x2 dx\int\frac{x}{\sqrt{1-x^2}}\,\mathrm{d}x for ∣x∣<1|x|<1.3 marks
See the full worksheet

Written by the Exaim team, led by Shaun Daswani (Head of Upper Secondary, Improve ME Institute; MSc Financial Mathematics, Imperial College London; BSc, UCL) and Jason Daswani (operational lead, Improve ME Institute; LSE).