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Derivative of \( \displaystyle \frac{\sqrt{16 x^{2} + 16 x + 5}}{4} \)

Problem 2.2002 · hard

Differentiate \( \displaystyle f(x) = \frac{\sqrt{16 x^{2} + 16 x + 5}}{4} \).
  1. \[ \frac{d}{d x} \frac{\sqrt{16 x^{2} + 16 x + 5}}{4} \]
    constant-multipleStart with the derivative of the function.✓ Proved
  2. \[ = \frac{\frac{d}{d x} \sqrt{16 x^{2} + 16 x + 5}}{4} \]
    constant-multiple rewriteFactor out the constant 1/4. Rewrite the square root as a fractional power.✓ Proved
  3. \[ = \frac{\frac{d}{d x} \left(16 x^{2} + 16 x + 5\right)}{8 \sqrt{16 x^{2} + 16 x + 5}} \]
    chain algebraApply the chain rule. Multiply the constants.✓ Proved
  4. \[ = \frac{32 x + 16}{8 \sqrt{16 x^{2} + 16 x + 5}} \]
    derivativeDifferentiate the polynomial inside.✓ Proved
  5. \[ = \frac{2 \left(2 x + 1\right)}{\sqrt{16 x^{2} + 16 x + 5}} \]
    algebraFactor out 16 from the polynomial.✓ Proved
  6. \[ = \frac{4 x + 2}{\sqrt{16 x^{2} + 16 x + 5}} \]
    algebra simplifySimplify the coefficients. Rewrite with a positive exponent and simplify.✓ Proved
Answer \( \frac{2 \left(2 x + 1\right)}{\sqrt{16 x^{2} + 16 x + 5}} \)

✓ 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
undefined where 16*x**2 + 16*x + 5 = 0
5✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
undefined where 16*x**2 + 16*x + 5 = 0
6✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
undefined where 16*x**2 + 16*x + 5 = 0
7✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
undefined where 16*x**2 + 16*x + 5 = 0
8✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
undefined where 16*x**2 + 16*x + 5 = 0
9✓ Provedsympy 1.14.0simplify(a - b) reduced to 0
undefined where 16*x**2 + 16*x + 5 = 0
answer✓ Provedsympy 1.14.0final line against the stated answer: simplify(a - b) reduced to 0
undefined where 16*x**2 + 16*x + 5 = 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 2026-10-10
  • qwen3.6:27b-mlx: pass 2026-10-10
  • gpt-oss:20b: pass 2026-10-10
  • qwen3.6:27b-mlx: pass 2026-10-10 — The solution correctly applies the constant multiple rule, chain rule, and algebraic simplifications in a step-by-step manner. Each step changes only one aspect of the expression and uses valid labels from the provided vocabulary.

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 2026-10-10 with SymPy 1.14.0.