Tìm nghiệm

a x-1/x - 1/x+1 = 2x-1/x^2+x
b /x-2/=3
c /x+1/=/2x+3/
d/3x/=x+6
e /x-5/=13-2x
f /5x-1/=x-12 
cac bn giup minh vs