Evaluate \(\int \frac{x^{3} + x + 1}{x^{2} - 1}\, dx\).
💡 Concept Hints
Identify the domain and the inner and outer functions, or the relevant one-sided limits.
Apply the appropriate differentiation or limit rule, keep all chain factors, and check exceptional points.
✅ Step-by-Step Solution
Final Answer: \(\frac{x^{2}}{2} + \frac{3 \log{\left(\left|{x - 1}\right| \right)}}{2} + \frac{\log{\left(\left|{x + 1}\right| \right)}}{2}\) + C.
Work on each open interval where the original integrand is real and defined.
Factor the denominator, perform polynomial division if needed, and solve for the partial-fraction coefficients.
The integrand rewrites as \(x + \frac{1}{2 \left(x + 1\right)} + \frac{3}{2 \left(x - 1\right)}\). Apply ∫xᵖdx=x^(p+1)/(p+1) for p≠−1, ∫dx/x=log|x|, and the elementary exponential/trigonometric rules.
An antiderivative is F(x)=\(\frac{x^{2}}{2} + \frac{3 \log{\left(\left|{x - 1}\right| \right)}}{2} + \frac{\log{\left(\left|{x + 1}\right| \right)}}{2}\).
Differentiate this expression to check that F′(x)=\(\frac{x^{3} + x + 1}{x^{2} - 1}\). Add an arbitrary constant C on each domain component.
Master Chapter 7: Integrals
Practise interactive questions, flashcards, visual mind maps, and timed board tests for Integrals.