设f(x)=lg【a-4/(x+2)】是奇函数,(1)求a?(2)求函数的定义域?

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设f(x)=lg【a-4/(x+2)】是奇函数,(1)求a?(2)求函数的定义域?
设f(x)=lg【a-4/(x+2)】是奇函数,(1)求a?(2)求函数的定义域?

设f(x)=lg【a-4/(x+2)】是奇函数,(1)求a?(2)求函数的定义域?
奇函数不是F (0)=0 把0带进去就解除a了

f(x)=lg【a-4/(x+2)】是奇函数
=> (a-4/(x+2))*( a-4/(-x+2))=1
即 [ ax+2(a-2) ]* [ ax – 2(a-2) ] = (x+2) * (x-2)
=> a=1
y=ln[ (x-2)/(x+2)]
定义域:(-∞,-2) U(2,+∞)a不该等于3么?f(x)=lg【a-4/(x+2)】...

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f(x)=lg【a-4/(x+2)】是奇函数
=> (a-4/(x+2))*( a-4/(-x+2))=1
即 [ ax+2(a-2) ]* [ ax – 2(a-2) ] = (x+2) * (x-2)
=> a=1
y=ln[ (x-2)/(x+2)]
定义域:(-∞,-2) U(2,+∞)

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