设f(x)连续,则d2/dx2∫0xtf(x-t)dt=________.

admin2021-10-18  13

问题 设f(x)连续,则d2/dx20xtf(x-t)dt=________.

选项

答案f(x)

解析 由∫0xtf(x-t)dt→∫x0(x-u)f(u)(-du)=x∫0xf(u)du-∫0xuf(u)du得d/dx∫0xtf(x-t)dt=d/dx[x∫0xf(u)du-∫0xuf(u)du]=∫0xf(u)du+xf(x)-xf(x)=∫0xf(u)du,故d2/dx20xtf(x-t)dt=d/dx∫0xf(u)du=f(x).
转载请注明原文地址:https://kaotiyun.com/show/bCy4777K
0

最新回复(0)