如何用Excel函数提取A列中第二组数字到B列答:方便的办法应该是通过分列操作。函数提取的方法是:在B2单元格中输入以下公式,然后向下填充公式 =MID(A2,FIND("座",SUBSTITUTE(A2," ","座",2)),FIND("座",SUBSTITUTE(A2," ","座",3))-FIND("座",SUBSTITUTE(A2," ","座",2)))详见附图附件 ...
1.已知集合A={1,2,3},B={4,5},则从A到B的函数f(x)有几个?怎么算,说下...答:(1)2*2*2=8 (2)f(ax+b)=(ax+b)^2+4(ax+b)+3=a^2x^2+(2ab+4a)x+(b^2+4b+3)=x^2+10x+24,所以a^2==1,2ab+4a=10,b^2+4b+3=24,三个式子联立,解得a=1,b=3,或者a=-1,b=-7,所以5a-b=2 设u=ax+b,这是内层函数,f(x)是外层函数,f(ax+b)=x^2+...