(y+3)/(y-1)-y/(y+1)=8/(y2-1)

Question

(y+3)/(y-1)-y/(y+1)=8/(y2-1)

Answer 1

((y + 3)*(y + 1) - y*(y - 1))/( (y - 1)*(y + 1) ) = 8/(y^2 - 1)
((y + 3)*(y + 1) - y*(y - 1))/(y^2 - 1) = (y^2 - 1) ( Так как (y - 1)*(y + 1) = y^2 - 1 ).
(y + 3)*(y + 1) - y*(y - 1) = 8
y^2 + 3*y + y + 3 - y^2 + y = 8
5*y = 5
y = 1