3.78*2.5/1.25*0.4/8怎么简便

来源:学生作业帮助网 编辑:六六作业网 时间:2024/05/04 20:22:39
3.78*2.5/1.25*0.4/8怎么简便3.78*2.5/1.25*0.4/8怎么简便3.78*2.5/1.25*0.4/8怎么简便3.78*2.5/1.25*0.4/8=3.78*(2.5*0

3.78*2.5/1.25*0.4/8怎么简便
3.78*2.5/1.25*0.4/8怎么简便

3.78*2.5/1.25*0.4/8怎么简便
3.78*2.5/1.25*0.4/8
=3.78*(2.5*0.4)/(1.25*8)
=3.78*1/10
=0.378

令p=2^x
则p>0
y=(a-p)/(1+p)
=-(p-a)/(p+1)
=-(p+1-a-1)/(p+1)
=-[(p+1)/(p+1)-(a+1)/(p+1)]
=-[1-(a+1)/(p+1)
=-1+(a+1)/(p+1)
p>0
p+1>1
0<1/(p+1)<1
a>-1
所以a+1>0
所以0<(a+1)/(p+1)-1+0<-1+(a+1)/(p+1)<-1+a+1
所以值域(-1,a)