Use Riemann sums to approximate the area bounded by the graph of

the lines x = -2 and x = 3 and the x-axis. Use *N* left-hand endpoints for
*N = 10* and *50*.

Using

- f:=x->x^3-5*x+7;
- with(student);
- leftbox(f(x), x = -2..3, 10);
- leftsum(f(x), x = -2..3, 10);
- evalf(");
- leftbox(f(x), x = -2..3, 50);