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Integral of \( \displaystyle \frac{6 x - 4}{- 2 x + \left(2 x - 1\right)^{2} + 1} \)

Problem 4.471 · hard

Find \( \displaystyle \int \frac{6 x - 4}{- 2 x + \left(2 x - 1\right)^{2} + 1} \, dx \). (Omit the constant of integration.)
  1. \[ \int \frac{6 x - 4}{- 2 x + \left(2 x - 1\right)^{2} + 1}\, dx \]
    integralStart with the integral of the given function.✓ Proved
  2. \[ = \int \frac{6 x - 4}{4 x^{2} - 6 x + 2}\, dx \]
    algebra simplifyExpand the squared term. Combine like terms in the denominator.✓ Proved
  3. \[ = \int \frac{3 x - 2}{2 x^{2} - 3 x + 1}\, dx \]
    algebraDivide the numerator and denominator by 2.✓ Proved
  4. \[ = \int \frac{3 x - 2}{\left(x - 1\right) \left(2 x - 1\right)}\, dx \]
    algebraFactor the quadratic denominator.✓ Proved
  5. \[ = \int \left(\frac{1}{2 x - 1} + \frac{1}{x - 1}\right)\, dx \]
    partial-fractionsPerform partial fraction decomposition.✓ Proved
  6. \[ = \int \frac{1}{x - 1}\, dx + \int \frac{1}{2 x - 1}\, dx \]
    linearitySplit the integral into two parts.≈ Checked numerically
  7. \[ = \ln{\left(x - 1 \right)} + \frac{\ln{\left(2 x - 1 \right)}}{2} \]
    antiderivativeIntegrate both terms using the substitution rule.✓ Proved
Answer \( \ln{\left(x - 1 \right)} + \frac{\ln{\left(x - \frac{1}{2} \right)}}{2} + C \)

✓ Nihil obstat Lines: 7 proved, 2 checked numerically. The answer was also checked a second way, without looking at the solution. Reviewers found nothing wrong with the explanation.

The full receipt
LineStatusChecked byDetail
1✓ Provedsympy 1.14.0line 1 is the problem as stated
2✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
undefined where -2*x + (2*x - 1)**2 + 1 = 0
undefined where 4*x**2 - 6*x + 2 = 0
3✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
undefined where 4*x**2 - 6*x + 2 = 0
4✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
undefined where 4*x**2 - 6*x + 2 = 0
undefined where 2*x**2 - 3*x + 1 = 0
5✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
undefined where 2*x**2 - 3*x + 1 = 0
undefined where 2*x - 1 = 0
undefined where x - 1 = 0
6✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
undefined where 2*x - 1 = 0
undefined where x - 1 = 0
7≈ Checked numericallysympy 1.14.0sympy 1.14.0: simplify left log(x - 1/2)/2 - log(2*x - 1)/2; numeric agreement only, at 24 of 24 sampled points
undefined where 2*x - 1 = 0
undefined where x - 1 = 0
8✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
undefined where 2*x - 1 = 0
undefined where x - 1 = 0
log is undefined for non-positive arguments
answer≈ Checked numericallysympy 1.14.0sympy 1.14.0: final line against the stated answer: simplify left -log(x - 1/2)/2 + log(2*x - 1)/2; numeric agreement only, at 24 of 24 sampled points
log is undefined for non-positive arguments
answer, a second way✓ Provedsympy 1.14.0SymPy differentiated the stated antiderivative back to the integrand

Reviewers

  • gpt-oss:20b: pass
  • qwen3.6:27b-mlx: pass — The solution correctly simplifies the integrand, performs partial fraction decomposition, and integrates term-by-term. The final answer is algebraically equivalent to the stated answer (using log properties to combine terms).
Every verdict on record (4)
  • gpt-oss:20b: pass 2026-10-06
  • qwen3.6:27b-mlx: pass 2026-10-06 — The solution correctly simplifies the integrand, performs partial fraction decomposition, and integrates term-by-term. The final answer is algebraically equivalent to the stated answer (using log properties to combine terms).
  • gpt-oss:20b: pass 2026-10-06
  • qwen3.6:27b-mlx: pass 2026-10-06 — The solution correctly simplifies the integrand, performs partial fraction decomposition, and integrates term-by-term. The final answer is algebraically equivalent to the stated answer (using log properties to combine terms), and all steps adhere to the single-rule constraint.

Proved: SymPy reduced the difference between the two sides to zero. Checked independently: a separate method, named above, confirmed it. Checked numerically: the two sides agree at every sampled point, which is evidence, not proof. Reviewed: a model or a person read it; that is all a sentence can have. Solution by gemma4:26b, checked 2026-10-06 with SymPy 1.14.0.