Derivative of \( \displaystyle - \frac{\sqrt{9 x^{2} - 18 x + 10}}{3} \)
Problem 2.1754 · hard
Differentiate \( \displaystyle f(x) = - \frac{\sqrt{9 x^{2} - 18 x + 10}}{3} \).
- \[ \frac{d}{d x} \left(- \frac{\sqrt{9 x^{2} - 18 x + 10}}{3}\right) \]derivativeStart with the derivative of the function.✓ Proved
- \[ = - \frac{\frac{d}{d x} \sqrt{9 x^{2} - 18 x + 10}}{3} \]constant rewritePull out the constant factor. Rewrite the square root as a fractional exponent.✓ Proved
- \[ = - \frac{\frac{d}{d x} \left(9 x^{2} - 18 x + 10\right)}{6 \sqrt{9 x^{2} - 18 x + 10}} \]chain algebraApply the chain rule. Multiply the constants.✓ Proved
- \[ = - \frac{18 x - 18}{6 \sqrt{9 x^{2} - 18 x + 10}} \]derivativeDifferentiate the inner polynomial.✓ Proved
- \[ = - \frac{3 \left(x - 1\right)}{\sqrt{9 x^{2} - 18 x + 10}} \]algebraFactor out 18 from the polynomial derivative.✓ Proved
- \[ = \frac{3 - 3 x}{\sqrt{9 x^{2} - 18 x + 10}} \]algebra simplifySimplify the coefficients. Rewrite with a positive exponent.✓ Proved
Answer \( \frac{3 \left(1 - x\right)}{\sqrt{9 x^{2} - 18 x + 10}} \)
✓ 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 undefined where 9*x**2 - 18*x + 10 = 0 |
| 5 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 undefined where 9*x**2 - 18*x + 10 = 0 |
| 6 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 undefined where 9*x**2 - 18*x + 10 = 0 |
| 7 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 undefined where 9*x**2 - 18*x + 10 = 0 |
| 8 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 undefined where 9*x**2 - 18*x + 10 = 0 |
| 9 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 undefined where 9*x**2 - 18*x + 10 = 0 |
| answer | ✓ Proved | sympy 1.14.0 | final line against the stated answer: simplify(a - b) reduced to 0 undefined where 9*x**2 - 18*x + 10 = 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
Every verdict on record (4)
gpt-oss:20b: pass 2026-10-07qwen3.6:27b-mlx: pass 2026-10-07gpt-oss:20b: pass 2026-10-07qwen3.6:27b-mlx: pass 2026-10-07
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 2026-10-07 with SymPy 1.14.0.