log(x+5)=log(x)+log(2) log(8)+log(x)=log(24) 2log(x)=log(2x)+log(3)

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log(x+5)=log(x)+log(2) log(8)+log(x)=log(24) 2log(x)=log(2x)+log(3)

log(x+5)=log(x)+log(2) log(8)+log(x)=log(24) 2log(x)=log(2x)+log(3)
log(x+5)=log(x)+log(2) log(8)+log(x)=log(24) 2log(x)=log(2x)+log(3)

log(x+5)=log(x)+log(2) log(8)+log(x)=log(24) 2log(x)=log(2x)+log(3)
log(x+5)=log(x)+log(2)
log(x+5)=log(2x)
x+5=2x
x=5
log(8)+log(x)=log(24)
log(8x)=log(24)
8x=24
x=3
2log(x)=log(2x)+log(3)
log(x²)=log(2x*3)
所以x²=2x*3
x(x-6)=0
x=0,x=6
真数大于0
所以x>0
所以x=6

log(x+5)=log(x)+log(2)
log(x+5)=log(2x)
x+5=2x
x=5
log(8)+log(x)=log(24)
log(8x)=log(24)
8x=24
x=3
2log(x)=log(2x)+log(3)
log(x²)=log(2x*3)
x²=2x*3 (...

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log(x+5)=log(x)+log(2)
log(x+5)=log(2x)
x+5=2x
x=5
log(8)+log(x)=log(24)
log(8x)=log(24)
8x=24
x=3
2log(x)=log(2x)+log(3)
log(x²)=log(2x*3)
x²=2x*3 (x>0)
x²=6x
x=6
ln(2x-5)*5=lnx²
(2x-5)*5=x²
10x-25=x²
x²-10x+25=0
(x-5)²=0
x=5
log(x-5)=log[7x/(x+4)]
(x-5)=7x/(x+4)
(x-5)(x+4)=7x
x²-x-20=7x
x²-8x-20=0
(x-10)(x+2)=0
x=10 x=-2(舍去)

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