Hans Georg Schaathun
Oktober 2016
$$I \approx T_1+T_2+T_3+T_4+T_5$$
$$T_1 = (x_1-x_0)\cdot(y_0+y_1)/2$$
$$T_i = (x_i-x_{i-1})\cdot(y_{i-1}+y_i)/2$$
$$I \approx (x_1-x_0)\big(\frac{y_0}2+y_1+y_2+\ldots+y_{n-1}+ \frac{y_n}2\big)$$
$$I = R_1+R_2+R_3+R_4+R_5$$
$$R_1 = (x_1-x_0)\cdot y_1$$
$$R_i = (x_i-x_{i-1})\cdot y_i$$
$$I = (x_1-x_0)(y_1+y_2+\ldots+y_n)$$