Use definition to find the area of f(x)=5x-2x^3 on interval [6, -6]with four sample right side

Answer 1

Use WHAT definition? What do you mean by "four sample right side? Right side of what?

Area above what lower boundary?

Since f(x) = -f(-x), and the interval is symmetric about the origin, it seems to me there are equal areas below and above the x axis.