高数课程妥媒血课件 镭理工大理>> 且P(x,y)dx+Q(x,y) L ={Pp(,v()m'(t)+Q|m(),v()wy()t 特殊情形 (1)L:y=y(x)x起点为a,终点为b 则「PQ={Px,y(x)+Qx,y(x)y(x) L (2)L:x=x(y)y起点为c,终点为l 则∫Pd+Qb=Px,y()+Qx(y2y小 Http://www.heut.edu.cnP t t t Q t t t dt P x y dx Q x y dy L { [ ( ), ( )] ( ) [ ( ), ( )] ( )} ( , ) ( , )         =  +  +  且 (1) L : y = y(x) x起点为a，终点为b. Pdx Qdy {P[x, y(x)] Q[x, y(x)]y (x)}dx. b L a 则 + = +  (2) L : x = x( y) y起点为c，终点为d. Pdx Qdy {P[x( y), y]x ( y) Q[x( y), y]}dy. d L c 则 + =  + 特殊情形