Integration by substitution
What Integration by substitution means in Mathematics A-Level, as defined for AQA, Pearson Edexcel, WJEC.
Definitions of Integration by substitution
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Reference: AQA
A method that reverses the chain rule, limited to cases where one substitution will lead to a function which can be integrated.
Reverses the chain rule by choosing u = g(x), so du = g′(x) dx, and rewriting the integral in terms of u and du.
Transforms an integrand into a standard form by changing variables, letting u = g(x) so du = g'(x) dx.
Topics that use Integration by substitution
- H: Integration (AQA A-Level)
- Integration (Pearson Edexcel A-Level)
- Integration (A2 Unit 3: Pure Mathematics B) (WJEC A-Level)
Related terms
- Area between curves
- Definite integral
- Integration by parts
- Antiderivative
- Area under a curve
- Fundamental Theorem of Calculus
- limit of a sum
- separable variables
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