x^2-(y-z)^2/(x+y)^2-z^2化简

Question

x^2-(y-z)^2/(x+y)^2-z^2化简

Answer 1

用平方差公式a^2-b^2=(a+b)(a-b)
(x^2-(y-z)^2)/((x+y)^2-z^2)
=((x-y+z)*(x+y-z))/((x+y-z)*(x+y+z))
=(x-y+z)/(x+y+z)