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
\[ \frac{d}{dx}\left[\tan\left(x^{2} + 1\right)\right] = \frac{2 x}{\cos\left(x^{2} + 1\right)^{2}} \]
\[ f(x) = \tan\left(x^{2} + 1\right) \]
\[ g(x) = x^{2} + 1,\quad g'(x) = 2 x \]
\[ f'(x) = \left[\frac{1}{\cos\left(u\right)^{2}}\right]_{u=g(x)} \cdot g'(x) \]
\[ f'(x) = \frac{2 x}{\cos\left(x^{2} + 1\right)^{2}} \]
\[ f''(x) = \frac{2 \cos\left(x^{2} + 1\right)^{2} - 2 x 2 \cos\left(x^{2} + 1\right) -\left(\sin\left(x^{2} + 1\right) 2 x\right)}{\left(\cos\left(x^{2} + 1\right)^{2}\right)^{2}} \]Values of f and f' for tan( + 1)
| x | f(x) | f'(x) |
|---|---|---|
| -2 | -3.380515 | -49.711527 |
| -1 | -2.1850399 | -11.548798 |
| 0.5 | 3.0095697 | 10.05751 |
| 1 | -2.1850399 | 11.548798 |
| 2 | -3.380515 | 49.711527 |
| 3 | 0.64836083 | 8.5222306 |
Questions
What is the derivative of tan( + 1)?
The derivative of is .
What is the second derivative of tan( + 1)?
(2 * cos( + 1)^2 - 2x * 2cos( + 1) * -(sin( + 1) * 2x)) / (cos( + 1)^2)^2.
Which rule do you use for tan( + 1)?
The chain rule.
What is the slope of tan( + 1) at x = 1?
11.548798.