x²-y²/x²-(y-z)²÷x²+2xy+y²/(x-y)²-z²×x²+xy-xz/x²-xy

Question

x²-y²/x²-(y-z)²÷x²+2xy+y²/(x-y)²-z²×x²+xy-xz/x²-xy

Answer 1

原式=(X+Y)(X-Y)/(X+Y+Z)(X-Y+Z)*(X-Y+Z)(X-Y-Z)/(X+Y)^2*X(X+Y-Z)/X(X-Y)
=(X-Y-Z)/(X+Y)