Question

若y=y1+y2,且y1与x成反比例,y2与x-2成反比例,且当x=1时,y=-1 ；x=3时,y=5

Answer 1

y1与x成反比例,y2与x-2成反比例

可设y1=k/x y2=k'/(x-2)

则y=y1+y2=k/x+k'/(x-2)

当x=1时,y=-1

则-1=k+k'/(1-2) k-k'=-1 (1)

x=3时,y=5

则5=k/3+k'/(3-2) k/3+k'=5 (2)

(1)+(2) 4k/3=4 k=3

代入(1) k'=k+1=4

所以关于x的函数关系

y=3/x+4/(x-2)

希望能帮到你,祝学习进步O(∩_∩)O