1. Find dx/dt and dy/dt. 2. Substitute into the arc length formula. 3. Evaluate the integral.

1. Integrate to get [t]. 2. Evaluate at the bounds: $\pi - 0 = \pi$.

$S=\int_a^b \sqrt{(\tfrac{dx(t)}{dt})^2 + (\tfrac{dy(t)}{dt})^2} dt$

$S=\int_a^b \sqrt{1+[f'(x)]^2} dx$

The distance between two points along a curve.

A curve where the x and y coordinates are defined by functions of a parameter, usually denoted as t.

A curve in a plane that has a continuous first derivative.