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 chain rule.
- 2
Chain rule: differentiate the outer function, keep the inside, then multiply by the derivative of the inside. The inside is .
- 3
The outer function is tan(u); its derivative evaluated at g(x), times g'(x):
- 4
Simplify:
- 5
Differentiating once more gives the second derivative, which tells you about curvature:
LaTeX source of the formulas on this page
\[ \frac{d}{dx}\left[\tan\left(x^{3}\right)\right] = \frac{3 x^{2}}{\cos\left(x^{3}\right)^{2}} \]
\[ f(x) = \tan\left(x^{3}\right) \]
\[ g(x) = x^{3},\quad g'(x) = 3 x^{2} \]
\[ f'(x) = \left[\frac{1}{\cos\left(u\right)^{2}}\right]_{u=g(x)} \cdot g'(x) \]
\[ f'(x) = \frac{3 x^{2}}{\cos\left(x^{3}\right)^{2}} \]
\[ f''(x) = \frac{6 x \cos\left(x^{3}\right)^{2} - 3 x^{2} 2 \cos\left(x^{3}\right) -\left(\sin\left(x^{3}\right) 3 x^{2}\right)}{\left(\cos\left(x^{3}\right)^{2}\right)^{2}} \]Values of f and f' for tan()
| x | f(x) | f'(x) |
|---|---|---|
| -2 | 6.7997115 | 566.83291 |
| -1 | -1.5574077 | 10.276556 |
| 0.5 | 0.12565514 | 0.76184191 |
| 1 | 1.5574077 | 10.276556 |
| 2 | -6.7997115 | 566.83291 |
| 3 | -3.2737038 | 316.36269 |
Questions
What is the derivative of tan()?
The derivative of is .
What is the second derivative of tan()?
(6x * cos()^2 - 3 * * 2cos() * -(sin() * 3 * )) / (cos()^2)^2.
Which rule do you use for tan()?
The chain rule.
What is the slope of tan() at x = 1?
10.276556.