Find all relative extrema of the function. Use the second derivative test where applicable. (If an answer does not exist, enter DNE. .......................................................................................................... \[ f(x)=x+\frac{64}{x} \] relative maximum \( \quad(x, y)=(\square) \)
Solución de inteligencia artificial de Upstudy
Responder
Solución

¡Inicia sesión para desbloquear respuestas gratis!
Una plataforma de aprendizaje en la que confían millones de estudiantes y profesores reales.

Respondido por UpStudy AI y revisado por un tutor profesional
Bonus Knowledge
To find the relative extrema of the function \( f(x) = x + \frac{64}{x} \), we first find the first derivative and set it to zero. 1. **Find the first derivative:** \[ f'(x) = 1 - \frac{64}{x^2} \] Setting the first derivative to zero: \[ 1 - \frac{64}{x^2} = 0 \implies \frac{64}{x^2} = 1 \implies x^2 = 64 \implies x = 8 \text{ (only positive as } x \text{ must be positive for domain)} \] 2. **Find the second derivative:** \[ f''(x) = \frac{128}{x^3} \] Evaluating the second derivative at \( x=8 \): \[ f''(8) = \frac{128}{8^3} = \frac{128}{512} = \frac{1}{4} \] Since \( f''(8) > 0 \), there is a relative minimum at \( x = 8 \). 3. **Calculate \( y \) when \( x = 8 \):** \[ f(8) = 8 + \frac{64}{8} = 8 + 8 = 16 \] Thus, the relative minimum is: \[ \text{relative maximum } (x, y) = \text{DNE} \]
