设f(x)在[0,1]连续,且单调减少,f(x)>0,证明:对于满足0<α<β<1的任何α,β,有β∫α0f(x

设f(x)在[0,1]连续,且单调减少,f(x)>0,证明:对于满足0<α<β<1的任何α,β,有β∫α0f(x)dx>α∫βαf(x)dx.