Derivative of \( \displaystyle \left(2 x - \frac{2}{5}\right) e^{5 x} \)
Problem 2.1020 · medium
Differentiate \( \displaystyle f(x) = \left(2 x - \frac{2}{5}\right) e^{5 x} \).
- \[ \frac{d}{d x} \left(2 x - \frac{2}{5}\right) e^{5 x} \]Start with the derivative of the function.✓ Proved
- \[ = \frac{d}{d x} \left(2 x e^{5 x} - \frac{2 e^{5 x}}{5}\right) \]algebraDistribute the exponential term.✓ Proved
- \[ = \frac{d}{d x} 2 x e^{5 x} - \frac{d}{d x} \frac{2 e^{5 x}}{5} \]sumApply the difference rule.✓ Proved
- \[ = \frac{d}{d x} 2 x e^{5 x} - \frac{2 \frac{d}{d x} e^{5 x}}{5} \]constantPull out the constant factor.✓ Proved
- \[ = 2 x \frac{d}{d x} e^{5 x} + e^{5 x} \frac{d}{d x} 2 x - \frac{2 \frac{d}{d x} e^{5 x}}{5} \]productApply the product rule to the first term.✓ Proved
- \[ = 2 x \frac{d}{d x} e^{5 x} + 2 e^{5 x} - \frac{2 \frac{d}{d x} e^{5 x}}{5} \]derivativeDifferentiate 2*x.✓ Proved
- \[ = 10 x e^{5 x} \]chain algebra simplifyDifferentiate the exponential term using the chain rule. Simplify the products. Combine like terms.✓ Proved
Answer \( 10 x e^{5 x} \)
✓ 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
| Line | Status | Checked by | Detail |
|---|---|---|---|
| 1 | ✓ Proved | sympy 1.14.0 | line 1 is the problem as stated |
| 2 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 |
| 3 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 |
| 4 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 |
| 5 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 |
| 6 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 |
| 7 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 |
| 8 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 |
| 9 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 |
| answer | ✓ Proved | sympy 1.14.0 | final line against the stated answer: simplify(a - b) reduced to 0 |
| answer, a second way | ✓ Proved | sympy 1.14.0 | SymPy differentiated f directly and got the stated answer |
Reviewers
gpt-oss:20b: passqwen3.6:27b-mlx: pass — The solution correctly applies differentiation rules step-by-step, adhering to the single-change constraint and using valid labels from the fixed vocabulary.
Every verdict on record (4)
qwen3.6:27b-mlx: pass 2026-09-27 — The solution correctly applies differentiation rules step-by-step, adhering to the single-change constraint and using valid labels from the fixed vocabulary.gpt-oss:20b: pass 2026-09-27qwen3.6:27b-mlx: pass 2026-09-27 — The solution correctly applies the product rule, chain rule, and linearity of differentiation. Each step isolates a single operation, and the labels accurately reflect the rules applied.gpt-oss:20b: pass 2026-09-27
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 2026-09-27 with SymPy 1.14.0.