Derivative of
The derivative of is .
f(x) =
Type any function of x; the derivative is computed symbolically in your browser.
How to work it out
- 1
We differentiate with respect to x. The rule that applies is the quotient rule.
- 2
Quotient rule: . Let and .
- 3
Differentiate each piece:
- 4
Put them in the rule:
- 5
Simplify:
- 6
Differentiating once more gives the second derivative, which tells you about curvature:
LaTeX source of the formulas on this page
\[ \frac{d}{dx}\left[\frac{\arctan\left(x\right)}{x^{4}}\right] = \frac{\frac{x^{4}}{1 + x^{2}} - \arctan\left(x\right) 4 x^{3}}{\left(x^{4}\right)^{2}} \]
\[ f(x) = \frac{\arctan\left(x\right)}{x^{4}} \]
\[ u = \arctan\left(x\right),\quad v = x^{4} \]
\[ u' = \frac{1}{1 + x^{2}},\quad v' = 4 x^{3} \]
\[ f'(x) = \frac{\left(\frac{1}{1 + x^{2}}\right)\left(x^{4}\right) - \left(\arctan\left(x\right)\right)\left(4 x^{3}\right)}{\left(x^{4}\right)^{2}} \]
\[ f'(x) = \frac{\frac{x^{4}}{1 + x^{2}} - \arctan\left(x\right) 4 x^{3}}{\left(x^{4}\right)^{2}} \]
\[ f''(x) = \frac{\left(\frac{4 x^{3} \left(1 + x^{2}\right) - x^{4} 2 x}{\left(1 + x^{2}\right)^{2}} - \left(\frac{4 x^{3}}{1 + x^{2}} + \arctan\left(x\right) 12 x^{2}\right)\right) \left(x^{4}\right)^{2} - \left(\frac{x^{4}}{1 + x^{2}} - \arctan\left(x\right) 4 x^{3}\right) 2 x^{4} 4 x^{3}}{\left(\left(x^{4}\right)^{2}\right)^{2}} \]Values of f and f' for atan(x) /
| x | f(x) | f'(x) |
|---|---|---|
| -2 | -0.069196795 | -0.12589359 |
| -1 | -0.78539816 | -2.6415927 |
| 0.5 | 7.4183617 | -46.546894 |
| 1 | 0.78539816 | -2.6415927 |
| 2 | 0.069196795 | -0.12589359 |
| 3 | 0.015420318 | -0.019325856 |
Questions
What is the derivative of atan(x) / ?
The derivative of is .
What is the second derivative of atan(x) / ?
(((4 * * (1 + ) - * 2x) / (1 + )^2 - (4 * / (1 + ) + atan(x) * 12 * )) * ()^2 - ( / (1 + ) - atan(x) * 4 * ) * 2 * * 4 * ) / (()^2)^2.
Which rule do you use for atan(x) / ?
The quotient rule.
What is the slope of atan(x) / at x = 1?
-2.6415927.