3.计算 ·对光滑曲线弧L:x=p(),y=W(t),(≤t≤B), ds=(+w2dr ·对光滑曲线弧L:y=W(x)(a≤x≤b), Ld-rxws)1+w产Rd 对光滑曲线弧L:r=r(0)(a≤B≤阝)， f(x,)ds =["fr(0)sine,r(0)cos01(0)+(0)do BEIJING UNIVERSITY OF POSTS AND TELECOMMUNICATIONS PRESS 目录 返回 结束目录 上页 下页 返回 结束 3. 计算 • 对光滑曲线弧 L f (x, y)ds • 对光滑曲线弧 L f (x, y)ds   b a f (x,(x)) L f (x, y)ds f r r [ ( )sin , ( )cos ]         • 对光滑曲线弧 (t) (t) d t 2 2   1 (x) dx 2  ( ) ( ) d 2 2 r  r      f[ (t), (t)]