∫Calc Practice
Home›Calculus 1›Product rule›Problem 2.1190

Derivative of \( \displaystyle \left(x - 4\right) e^{x - 3} \)

Problem 2.1190 · medium

Differentiate \( \displaystyle f(x) = \left(x - 4\right) e^{x - 3} \).
  1. \[ \frac{d}{d x} \left(x - 4\right) e^{x - 3} \]
    derivativeStart with the derivative of the function.✓ Proved
  2. \[ = \frac{d}{d x} \left(x e^{x - 3} - 4 e^{x - 3}\right) \]
    algebraDistribute the term (x - 4).✓ Proved
  3. \[ = \frac{d}{d x} x e^{x - 3} - \frac{d}{d x} 4 e^{x - 3} \]
    sumApply the sum rule for derivatives.✓ Proved
  4. \[ = \frac{d}{d x} x e^{x - 3} - 4 \frac{d}{d x} e^{x - 3} \]
    constantPull out the constant factor 4.✓ Proved
  5. \[ = x \frac{d}{d x} e^{x - 3} + e^{x - 3} \frac{d}{d x} x - 4 \frac{d}{d x} e^{x - 3} \]
    productApply the product rule to the first term.✓ Proved
  6. \[ = x \frac{d}{d x} e^{x - 3} + e^{x - 3} - 4 \frac{d}{d x} e^{x - 3} \]
    derivativeDifferentiate x.✓ Proved
  7. \[ = x e^{x - 3} - 3 e^{x - 3} \]
    exponentialDifferentiate the exponential term.✓ Proved
  8. \[ = \left(x - 4\right) e^{x - 3} + e^{x - 3} \]
    algebraCombine the terms involving exp(x - 3).✓ Proved
  9. \[ = \left(x - 3\right) e^{x - 3} \]
    algebra simplifyFactor out exp(x - 3). Simplify the expression.✓ Proved
Answer \( \left(x - 3\right) e^{x - 3} \)

✓ Nihil obstat Every line of this solution was proved by the computer algebra system SymPy. 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
3✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
4✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
5✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
6✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
7✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
8✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
9✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
10✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
answer✓ Provedsympy 1.14.0final line against the stated answer: simplify(a - b) reduced to 0
answer, a second way✓ Provedsympy 1.14.0SymPy differentiated f directly and got the stated answer

Reviewers

  • gpt-oss:20b: pass
  • qwen3.6:27b-mlx: pass
Every verdict on record (4)
  • qwen3.6:27b-mlx: pass 2026-09-29
  • gpt-oss:20b: pass 2026-09-29
  • qwen3.6:27b-mlx: pass 2026-09-29
  • gpt-oss:20b: pass 2026-09-29

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 2026-09-29 with SymPy 1.14.0.