Please help calculate all critical points and inflection points of f(x) = 4x5 − 5x4 and f(x) = x4 + 4x3. Apply the second derivative test at each critical point. Help find the open intervals on the x-axis on which the function is increasing and those on which it is decreasing please.

Differentiate the function ƒ(x)=(4x+3/5x−2​)^3.

Find the range of values of x for which f(x)=x^3-5x^2-8x+2 is decreasing.

Determine if the following functions are one-to-one by inspecting their graphs using the Vertical line test (VLT) and the Horizontal Line Test (HLT). You do not need to sketch the graphs. I am still have troubling solving these one...  16.) Y= 2x^3-4x^2-3x+517.) Y=x^2, X greater than or equal to 0