The graph of e−t2 is always positive. The area under the curve therefore will be positive for the interval 0<x<3.
h′(x) is therefore always positive, and the graph of h is increasing on the interval.
By the second fundamental theorem of calculus,
h′(x)=0∫xe−t2 dt
h′′(x)=e−x2
Similar to the previous case, the exponential function is positive for all values. Therefore, h is also concave up on the interval.