Approximate the Area Under the Graph Of $f(x)=2 x^{2}-1$ From $x=1$ To $x=5$

Short Answer

Approximate the area under the graph of $f(x)=2 x^{2}-1$ from $x=1$ to $x=5$ and above the $x$ -axis, using four rectangles. Let the height of each rectangle be the function value at the midpoint of the interval.