解方程:log2(3-x) - log4(x+5) =1

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解方程:log2(3-x) - log4(x+5) =1
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解方程:log2(3-x) - log4(x+5) =1
解方程:log2(3-x) - log4(x+5) =1

解方程:log2(3-x) - log4(x+5) =1
log2(3-x) - log4(x+5) =1
log2(3-x)=1+log4(x+5)
log4 (3-x)²=log4 4(x+5)
(3-x)²=4(x+5)
x²-6x+9=4x+20
x²-10x-11=0
(x-11)(x+1)=0
x=11或x=-1
经检验,x=11是增根(不满足真数大于0)
所以 x=-1