How do you Use the trapezoidal rule with four equal subdivisions to approximate a definite integral?

1 Answer
Sep 28, 2014

First split the interval [a,b] into 4 equal subintervals:

[x_0,x_1],[x_1,x_2],[x_2,x_3], and [x_3,x_4].

(Note: x_0=a and x_4=b)

The definite integral

int_a^b f(x)dx

can be approximated by

T_4=[f(x_0)+2f(x_1)+2f(x_2)+2f(x_3)+f(x_4)]cdot{Delta x}/{2},

where Delta x={b-a}/4.

I hope that this is helpful.