Solve $f''(x) = 0$ or find where $f''(x)$ is undefined.
What is the formula for the second derivative test?
1. Find critical points using $f'(x)$. 2. Plug critical points into $f''(x)$. 3. Determine local min/max based on the sign of $f''(x)$.
How to find local extrema using the Second Derivative Test?
1. Find critical points. 2. Compute the second derivative. 3. Evaluate the second derivative at each critical point. 4. Determine if each point is a local max, min, or neither.
Steps to determine concavity of a function.
1. Find the second derivative, $f''(x)$. 2. Set $f''(x) = 0$ and solve for x. 3. Create a sign chart for $f''(x)$. 4. Determine intervals of concave up ($f''(x) > 0$) and concave down ($f''(x) < 0$).
How to find inflection points?
1. Find the second derivative, $f''(x)$. 2. Set $f''(x) = 0$ and solve for x. 3. Check if the concavity changes at each potential inflection point.
What to do if the Second Derivative Test is inconclusive?
Use the First Derivative Test or analyze the behavior of the function around the critical point.
How to use the second derivative to determine if $x = c$ is a local max?
Find $f'(x)$, set $f'(c) = 0$ to confirm c is a critical point. Then, find $f''(x)$ and evaluate $f''(c)$. If $f''(c) < 0$, then $x = c$ is a local max.
How to use the second derivative to determine if $x = c$ is a local min?
Find $f'(x)$, set $f'(c) = 0$ to confirm c is a critical point. Then, find $f''(x)$ and evaluate $f''(c)$. If $f''(c) > 0$, then $x = c$ is a local min.
How to find the global extremum given one critical point?
If the function is continuous and has only one critical point, and that point is a local extremum, then it's also the global extremum.
How to find critical points for $f(x) = 4sin(x)$ on $0 < x < 2\pi$?
1. Find $f'(x) = 4cos(x)$. 2. Set $4cos(x) = 0$. 3. Solve for x, which gives $x = \frac{\pi}{2}, \frac{3\pi}{2}$.
Given $f(x) = 4sin(x)$ and critical point $x = \frac{\pi}{2}$, how to determine if it's a local max or min?
1. Find $f''(x) = -4sin(x)$. 2. Evaluate $f''(\frac{\pi}{2}) = -4$. 3. Since $f''(\frac{\pi}{2}) < 0$, it's a local max.
How to determine the nature of critical points when $f'(x) = \frac{247}{x}$?
1. Set $f'(x) = 0$ to find critical points, but there are none. 2. Check where $f'(x)$ is undefined, which is at $x=0$. 3. Since $f(x)$ is not defined at $x=0$, there are no local extrema.
Explain the relationship between concavity and the second derivative.
If $f''(x) > 0$, the function is concave up. If $f''(x) < 0$, the function is concave down.
How does the Second Derivative Test help find local extrema?
It uses the sign of the second derivative at critical points to determine if they are local maxima or minima.
Explain why $f''(x) > 0$ at a local minimum.
At a local minimum, the function is concave up, resembling the bottom of a bowl, thus $f''(x) > 0$.
Explain why $f''(x) < 0$ at a local maximum.
At a local maximum, the function is concave down, resembling the top of a hill, thus $f''(x) < 0$.
What does it mean if the Second Derivative Test is inconclusive?
The test doesn't provide enough information to determine the nature of the critical point. The critical point may be a point of inflection, a local extremum, or neither.
When should you use the First Derivative Test instead of the Second Derivative Test?
When the second derivative is difficult to compute or when $f''(c) = 0$.
Describe the relationship between critical points and extrema.
Extrema (local max or min) can only occur at critical points or endpoints of the interval.
Explain how to find critical points of a function.
Find where the first derivative is equal to zero or undefined.
What does it mean for a function to be concave up?
The slope of the tangent line is increasing as x increases.
What does it mean for a function to be concave down?
The slope of the tangent line is decreasing as x increases.