Question

已知y=y1+y2,y1与x成正比y2与x成反比,且当x=3时y=10/3 ,x=-2y=-5/2求y与x关系式

Answer 1

y1=ax

y2=b/x

当x=3时 y=y1+y2=ax+b/x=3a+b/3=10/3

当x=-2 y=y1+y2=ax+b/x=-2a-b/2=-5/2

得 a=1 b=1

y=y1+y2=x+1/x