第1个回答 2019-08-17
(1)设y1=ax1+b,把点(1,0.5)和(2,0.75)带入;
得:0.5=a+b ①式,0.75=2a+b ②式;
②式-①式的 a=0.25;即 b=0.25;
y1=0.25x1+0.25;
设y2=k根号x2,把点(4,2.5)带入;
得:2.5=k*根号4,即2k=2.5,k=1.25,;
y2=1.25根号x2;
(2)总利润W=y1+y2,其中x1+x2=10,x1=10-x2;
W=0.25(10-x2)+0.25+1.25根号x2;
令根号x2=x,即x2=x^2;
W=-0.25x^2+1.25x+2.75;
函数开口向下,即当x=-b/2a时,利润最大;
即x=1.25/0.5=2.5时,x2=6.25,x1=3.75,
利润最大为4.3125本回答被提问者采纳