已知X>Y,x2+Y2=4xy.求(X+Y)/(X-Y)=?

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已知X>Y,x2+Y2=4xy.求(X+Y)/(X-Y)=?
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已知X>Y,x2+Y2=4xy.求(X+Y)/(X-Y)=?
已知X>Y,x2+Y2=4xy.求(X+Y)/(X-Y)=?

已知X>Y,x2+Y2=4xy.求(X+Y)/(X-Y)=?
x²+y²-2xy=2xy
(x-y)²=2xy
x²+y²+2xy=6xy
(x+y)²=6xy
(x+y)²/(x-y)²=3
又因为x>y,x-y>0
(x+y)/(x-y)=√3

(x-y)2=2xy,(x+y)2=6xy,再开方,可得答案为3开根号,手机答的

(x+y)^2=6xy
(x-y)^2=2xy
x>y
(x+y)(x-y)=根下3