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
\[ \frac{d}{dx}\left[\frac{x^{3}}{\sqrt{x}}\right] = \frac{3 x^{2} \sqrt{x} - x^{3} \frac{1}{2 \sqrt{x}}}{\sqrt{x}^{2}} \]
\[ f(x) = \frac{x^{3}}{\sqrt{x}} \]
\[ u = x^{3},\quad v = \sqrt{x} \]
\[ u' = 3 x^{2},\quad v' = \frac{1}{2 \sqrt{x}} \]
\[ f'(x) = \frac{\left(3 x^{2}\right)\left(\sqrt{x}\right) - \left(x^{3}\right)\left(\frac{1}{2 \sqrt{x}}\right)}{\left(\sqrt{x}\right)^{2}} \]
\[ f'(x) = \frac{3 x^{2} \sqrt{x} - x^{3} \frac{1}{2 \sqrt{x}}}{\sqrt{x}^{2}} \]
\[ f''(x) = \frac{\left(6 x \sqrt{x} + 3 x^{2} \frac{1}{2 \sqrt{x}} - \left(3 x^{2} \frac{1}{2 \sqrt{x}} + x^{3} \frac{-\left(2 \frac{1}{2 \sqrt{x}}\right)}{\left(2 \sqrt{x}\right)^{2}}\right)\right) \sqrt{x}^{2} - \left(3 x^{2} \sqrt{x} - x^{3} \frac{1}{2 \sqrt{x}}\right) 2 \sqrt{x} \frac{1}{2 \sqrt{x}}}{\left(\sqrt{x}^{2}\right)^{2}} \]Values of f and f' for / sqrt(x)
| x | f(x) | f'(x) |
|---|---|---|
| 0.5 | 0.1767767 | 0.88388348 |
| 1 | 1 | 2.5 |
| 2 | 5.6568542 | 7.0710678 |
| 3 | 15.588457 | 12.990381 |
Questions
What is the derivative of / sqrt(x)?
The derivative of is .
What is the second derivative of / sqrt(x)?
((6x * sqrt(x) + 3 * * 1 / (2sqrt(x)) - (3 * * 1 / (2sqrt(x)) + * -(2 * 1 / (2sqrt(x))) / (2sqrt(x))^2)) * sqrt(x)^2 - (3 * * sqrt(x) - * 1 / (2sqrt(x))) * 2sqrt(x) * 1 / (2sqrt(x))) / (sqrt(x)^2)^2.
Which rule do you use for / sqrt(x)?
The quotient rule.
What is the slope of / sqrt(x) at x = 1?
2.5.