### Home > CALC > Chapter 2 > Lesson 2.1.2 > Problem 2-28

2-28.

Set up an equation using the Trapezoidal Rule that will approximate the area under *f*(*x*) = cos *x* on *x* is an even function to save yourself some work? Homework Help ✎

Notice the symmetry about the *y*-axis. If we evaluate the trapezoidal sum on one side of the *y*-axis, can we determine the trapezoidal sum on the other side of the *y*-axis?