已知2lg((x-y)/2)=lg x+lg y,求log (3-2√2),(x/y)求log (3-2√2)^(x/y)

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已知2lg((x-y)/2)=lg x+lg y,求log (3-2√2),(x/y)求log (3-2√2)^(x/y)
已知2lg((x-y)/2)=lg x+lg y,求log (3-2√2),(x/y)
求log (3-2√2)^(x/y)

已知2lg((x-y)/2)=lg x+lg y,求log (3-2√2),(x/y)求log (3-2√2)^(x/y)
2lg((x-y)/2)=lg x+lg y
有意义,则需
x-y>0,x>0,y>0 x/y>1
原式可化为:
lg((x-y)/2)^2=lg(xy)
∴(x-y)²/4=xy
∴x²-2xy+y²=4xy
x²-6xy+y²=0
两边同时除以y²
(x/y)²-6(x/y)+1=0
用求根公式解得
x/y=3±2√2
∵x/y>1
∴x/y=3+2√2
∵(3-2√2)(3+2√2)=1
∴log (3-2√2)(x/y)
=log (3-2√2)(3+2√2)
=-1

....后面什么符号?log (3-2√2) “ ,” ? (x/y)