Figure 1 below shows the curve y=e2xy = e^{2x}y=e2x for x>0x > 0x>0. The point P(x,y)P(x, y)P(x,y) lies on the curve, and the rectangle shown shaded has height y y\,y and width δx\delta xδx.
Find the exact value of
limδx→0∑x=25e2x δx\displaystyle\lim_{\delta x \to 0}\sum_{x=2}^{5} e^{2x}\,\delta xδx→0limx=2∑5e2xδx