解方程:log2(x+4)+log2(x-1)=1+log2(x+8)

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解方程:log2(x+4)+log2(x-1)=1+log2(x+8)
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解方程:log2(x+4)+log2(x-1)=1+log2(x+8)
解方程:log2(x+4)+log2(x-1)=1+log2(x+8)

解方程:log2(x+4)+log2(x-1)=1+log2(x+8)
由x+4>0,x-1>0,x+8>0得x>1
∵log2(x+4)+log2(x-1)=log2(2)+log2(x+8)
∴log2(x+4)(x-1)=log2(x+8)*2,
即(x+4)(x-1)=2(x+8)
解得x=4,x=-5(舍去)
∴log2(x+4)+log2(x-1)=1+log2(x+8)的解为:x=4

log2^(x+4)+log2^(x-1)=1+log2^(x+8)
先把1化为log2^2
log2^(x+4)+log2^(x-1)=log2^2+log2^(x+8)
log2^(x+4)(x-1)=log2^2(x+8)
∴(x+4)(x-1)=2(x+8)
整理得(x-4)(x+5)=0
解得x=4,x=-5(舍去)

log2(x+4)(x-1)=log2(x+8)*2, 即(x+4)(x-1)=2(x+8)解得x=4,x=-5(舍)