Question

X的平方—Y的平方—2XY=0求X,与Y的关系,怎么算?

Answer 1

x^2-y^2-2xy=0

x^2-2xy+y^2-2y^2=0

(x-y)^2-2y^2=0

(x-y+√2y)(x-y-√2y)=0

得 x=(-√2+1)y

或 x=(√2+1)y