计算二重积分I=∫∫0≤x≤π,0≤y≤πsin2xsin2ydxdy.
【正确答案】:I=∫0πdx∫0πsin2xsin2ydy
=(∫0πsin2xdx)2
={∫0π[(1-cos2x)/2]dx}2,
=[(1/2)x∣0π-1/4∫0πcos2xd(2x)]c
=[π/2-(1/4)sin2x∣0π]2
=π2/4
计算二重积分I=∫∫0≤x≤π,0≤y≤πsin2xsin2ydxdy.
- 2024-11-07 09:08:28
- 高等数学(经管类)(13125)