Trap Rule for sin(x) 
Use the trapezoidal rule with $N=6$ to approximate the arc length of the curve $f(x) = \sin(x)$ from $x=0$ to $x=\pi$.

So I found that $\Delta x = \frac{\pi}{6}$ which means that my interval points are $0,\frac{\pi}{3}, \frac{\pi}{2}, \frac{2\pi}{3}, \frac{5\pi}{6}$ and $\pi$.
Is that right?
And then after that I just use the trap rule forumula computing the value of $\sin$ of all my interval points.
Is my thinking correct?

The formula for step size is given by: 
$$\displaystyle h = \frac{b-a}{N} = \frac{\pi - 0}{6} = \frac{\pi}{6}$$
We are also given that $x_0 = 0$.
