Use the substitution u=1+2exu = 1 + 2e^xu=1+2ex to find ∫e3x1+2exdx\displaystyle \int \frac{e^{3x}}{1 + 2e^x} dx∫1+2exe3xdx.
Practise Edexcel A Level Maths Integration with exam-style questions for A Level Maths. 483 questions covering 13.1 Integrating x^n, 13.2 Indefinite Integrals, 13.3 Finding Functions, 13.4 Definite Integrals, 13.5 Areas under Curves, 13.6 Areas under the x-axis, and 13.7 Areas between curves and lines, matched to the Edexcel A Level Maths (9MA0) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.
