Question

若x,y为实数，且y=(根号（2x+1/3-4x))+(根号（2x+1/4x-3))+1,求x+yx+x^2y的值

求的是x+yx+x的平方*2y,别看错了，望高手解决。

Answer 1

y=(根号（))+(根号（2x+1/4x-3))+1
2x+1/3-4x=-(2x+1)/(4x-3)>=0
2x+1/4x-3>=0
3-4x≠0
∴2x+1=0
x=-1/2
得y=1
x+yx+x的平方*2y
=-1/2-1/2+1/4*2=-1/2

Answer 2

y=(根号（))+(根号（2x+1/4x-3))+1
2x+1/3-4x=-(2x+1)/(4x-3)>=0
2x+1/4x-3>=0
3-4x≠0
∴2x+1=0
x=-1/2
得y=1
x+yx+x的平方*2y
=-1/2-1/2+1/4*2=-1/2