Consider the following function.
\(y = x^4 - 2x^2 + 5\)
Find \(y'(x)\).
\(y'(x) = 4x^3 - 4x\)
The graph of \(y(x)\) has a horizontal tangent line when \(y'(x)\) is equal to what value?
\(y'(x) = 4x(x^2 - 1)\)
Set \(y'(x)\) equal to the value above and solve for \(x\). (Enter your answers as a comma-separated list.)
\(x = -1, 0, 1\)
Determine the points at which the graph of the function below has a horizontal tangent line.
smallest x-value \((x, y) = (-1, 8)\)
\((x, y) = (0, 5)\)
largest x-value \((x, y) = (1, 4)\)
