Derivative of \( \displaystyle \operatorname{atan}^{2}{\left(3 x - 3 \right)} \)
Problem 2.570 · medium
Differentiate \( \displaystyle f(x) = \operatorname{atan}^{2}{\left(3 x - 3 \right)} \).
- \[ \frac{d}{d x} \operatorname{atan}^{2}{\left(3 x - 3 \right)} \]Start with the derivative of the function.✓ Proved
- \[ = 2 \operatorname{atan}{\left(3 x - 3 \right)} \frac{d}{d x} \operatorname{atan}{\left(3 x - 3 \right)} \]powerApply the power rule.✓ Proved
- \[ = \frac{2 \operatorname{atan}{\left(3 x - 3 \right)} \frac{d}{d x} \left(3 x - 3\right)}{\left(3 x - 3\right)^{2} + 1} \]chainApply the chain rule to the inner function.✓ Proved
- \[ = \frac{6 \operatorname{atan}{\left(3 x - 3 \right)}}{\left(3 x - 3\right)^{2} + 1} \]derivative algebraDifferentiate the linear term 3*x - 3. Simplify the expression by multiplying the constants.✓ Proved
- \[ = \frac{6 \operatorname{atan}{\left(3 x - 3 \right)}}{9 x^{2} - 18 x + 10} \]algebra simplifyExpand the squared term. Combine like terms in the denominator.✓ Proved
Answer \( \frac{6 \operatorname{atan}{\left(3 x - 3 \right)}}{\left(3 x - 3\right)^{2} + 1} \)
✓ 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 undefined where (3*x - 3)**2 + 1 = 0 |
| 4 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 undefined where (3*x - 3)**2 + 1 = 0 |
| 5 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 undefined where (3*x - 3)**2 + 1 = 0 |
| 6 | ✓ Proved | sympy 1.14.0 | simplify(a - b) reduced to 0 undefined where (3*x - 3)**2 + 1 = 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 |
| answer | ✓ Proved | sympy 1.14.0 | final line against the stated answer: simplify(a - b) reduced to 0 undefined where (3*x - 3)**2 + 1 = 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 the power rule, chain rule, and derivative of arctangent in separate steps. The final simplification steps are algebraic and correctly labeled.
Every verdict on record (4)
qwen3.6:27b-mlx: pass 2026-09-21 — The solution correctly applies the power rule, chain rule, and derivative of arctangent in separate steps. The final simplification steps are algebraic and correctly labeled.gpt-oss:20b: pass 2026-09-21qwen3.6:27b-mlx: pass 2026-09-21gpt-oss:20b: pass 2026-09-21
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 2026-09-26 with SymPy 1.14.0.