For the function, find a form ula for the Riem ann sum obtained by dividing the interval [a,b] into n subintervals and using the right-hand endpointsfor each x i
​
. Then take a lim it of these sum s as n→[infinity] to calculate the area under the curve over [a,b]. Sketch a diagram of the region. f(x)=x 2
āˆ’x 3
,[āˆ’1,0]