a)Find the derivative of each the following functions.
f(x) = cos(x)/ 2x2
y = ln(x2 ? 11x + 30)
f(x) = e5x sin(2x)
b) Find the stationary points of the function y = x3 ? 12x + 11.
• Use a sign diagram to classify each of the stationary points.
• Use the second derivative test to classify each of the stationary points.
• Explain which method you prefer and why