x∈(0,1),1-x>0∵1/x+4/(1-x)=(1-x+x)/x+4(1-x+x)/(1-x)=1+(1-x)/x+4+4x/(1-x)=5+(1-x)/x+4x/(1-x)≧5+2√[(1-x)/x*4x/(1-x)]=5+4=9当且仅当:(1-x)/x=4x/(1-x)当x=1/3时,1/x+4/(1-x)最小值为9,所以m最大值为9...