題目 Problem Trochoid x=2θ−sinθx=2\theta-\sin\thetax=2θ−sinθ, y=2−cosθy=2-\cos\thetay=2−cosθ. Find the area under the curve and above the xxx-axis for 0≤θ≤2π0\le\theta\le 2\pi0≤θ≤2π. 解答
