∫Calc Practice
Home›Calculus 1›Product rule›Problem 2.2170

Derivative of \( \displaystyle \frac{e^{4 x} \sin{\left(4 x \right)}}{4} - \frac{e^{4 x} \cos{\left(4 x \right)}}{4} \)

Problem 2.2170 · hard

Differentiate \( \displaystyle f(x) = \frac{e^{4 x} \sin{\left(4 x \right)}}{4} - \frac{e^{4 x} \cos{\left(4 x \right)}}{4} \).
  1. \[ \frac{d}{d x} \left(\frac{e^{4 x} \sin{\left(4 x \right)}}{4} - \frac{e^{4 x} \cos{\left(4 x \right)}}{4}\right) \]
    derivativeStart with the derivative of the function.✓ Proved
  2. \[ = \frac{d}{d x} \frac{e^{4 x} \sin{\left(4 x \right)}}{4} - \frac{d}{d x} \frac{e^{4 x} \cos{\left(4 x \right)}}{4} \]
    sumApply the sum rule.✓ Proved
  3. \[ = \frac{\frac{d}{d x} e^{4 x} \sin{\left(4 x \right)}}{4} - \frac{\frac{d}{d x} e^{4 x} \cos{\left(4 x \right)}}{4} \]
    constant-multiple algebraFactor out the constant 1/4. Factor out 1/4 from both terms.✓ Proved
  4. \[ = \frac{e^{4 x} \frac{d}{d x} \sin{\left(4 x \right)}}{4} - \frac{e^{4 x} \frac{d}{d x} \cos{\left(4 x \right)}}{4} + \frac{\sin{\left(4 x \right)} \frac{d}{d x} e^{4 x}}{4} - \frac{\cos{\left(4 x \right)} \frac{d}{d x} e^{4 x}}{4} \]
    productApply the product rule to both terms.✓ Proved
  5. \[ = e^{4 x} \sin{\left(4 x \right)} - e^{4 x} \cos{\left(4 x \right)} + \frac{e^{4 x} \frac{d}{d x} \sin{\left(4 x \right)}}{4} - \frac{e^{4 x} \frac{d}{d x} \cos{\left(4 x \right)}}{4} \]
    exponentialDifferentiate the exponential term.✓ Proved
  6. \[ = 2 e^{4 x} \sin{\left(4 x \right)} \]
    trig algebra algebra simplify simplifyDifferentiate the trigonometric terms. Distribute the terms inside the parentheses. Remove the inner parentheses. Combine like terms. Final simplification.✓ Proved
Answer \( 2 e^{4 x} \sin{\left(4 x \right)} \)

✓ 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
11✓ 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)
  • gpt-oss:20b: pass 2026-10-13
  • qwen3.6:27b-mlx: pass 2026-10-13
  • gpt-oss:20b: fail (style) 2026-10-13 — Step 5 applies the product rule to two separate products in a single line, violating the rule‑by‑step granularity requirement.
  • qwen3.6:27b-mlx: pass 2026-10-13 — The solution correctly applies differentiation rules step-by-step, adhering to the one-change-per-step constraint. The labels used are appropriate for the operations performed.

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 2026-10-13 with SymPy 1.14.0.