Question

已知（2X)²=16,Y是（-5）²的算是平方根,求代数式x/x+y+x/x-y的值

Answer 1

|2x|=4,|x|=2

y=(-5)^2^(1/2)=5

x=2,y=5

x/(x+y)+x/(x-y)=2/7+2/(-3)=-8/21

x=-2,y=5

x/(x+y)+x/(x-y)=-2/3-2/(-7)=-8/21