求二重积分∫∫Dsiny/ydxdy,其中D由y=x^(1/2)和y=^x围成.

曲线y=√x与直线y=x的交点为(0,0)和(1,1)
于是积分区域D={(x,y)|y²≤x≤y,0≤y≤1}
从而原式=∫[0,1]siny/ydy∫[y²,y] 1 dx
=∫[0,1] sinydy-∫[0,1]ysinydy
=1-cos1-[-cos1+sin1]
=1-sin1