解方程:(1)log2^x log2^(x-1)=1

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解方程:(1)log2^x log2^(x-1)=1
解方程log2^(4^x+4)=x+log2^[2^(x+1)-3]

log2^(4^x+4)=x+log2^[2^(x+1)-3]log2^(4^x+4)-log2^[2^(x+1)-3]=xlog2[(4^x+4)/(2^(x+1)-3)]=x(4^x+4)/(2^

解方程log2(4^x+1)=x+log2(2^(x+3)-6)

log2(4^x+1)=x+log2[2^(x+3)-6]移项log2(4^x+1)-log2[2^(x+3)-6]=xlog2[(4^x+1)/(2^x×8-6)]=x即2^x=(4^x+1)/(2

方程log2(2^x+1)log2(2^x+1)=2的解为

则有log2(2^x+1)=正负根号下2所以当log2(2^x+1)=根号下2时.2^x+1=2^根号下2时则x=log2[(2^根号下2时)-1]同理为log2(2^x+1)负根号下2时x=log2

解方程log4(2-x)=log2(x-1)-1

先换成同底的log4(2-x)=log4(x-1)^2-log44化简一下log4(2-x)=log4[(x-1)^2/4]然后2-x=(x-1)^2/4结果是x=2或-42舍掉(因为真数是0)-4也

解方程log根号2(x+1)-log2(x+5/2)=1

log根号2(x+1)-log2(x+5/2)=1log2(x+1)²-log2(x+5/2)=1log2(x+1)²/(x+5/2)=1所以(x+1)²/(x+5/2)

解方程log2(9x-1-5)=log2(3x-1-2)-2.

log2(9x-1-5)=log2(3x-1-2)-2.∴log2(9x-1-5)=log2(3x-1-2)-log24.∴log2(9x-1-5)=log24(3x-1-2).∴9x-1-5=4(3

解方程log2(2-x)=log2(x-1)+1

log2(2-x)=log2(x-1)+log(2)log2(2-x)=log2[2(x-1)]2-x=2x-2x=4/3带入检验,成立所以x=4/3

解方程 log2(2^(x+1)+2)=2/log2((2^x)+1)

具体过程嘛.我写关键步成吗.log2(2((2^x)+1)))=2/log2((2^x)+1)log2(2)+log2((2^x)+1)=2/log2((2^x)+1)1+log2((2^x)+1)=

解方程log2(x+14)-log2(x+6)=3-log2(x+2)

log2(x+14)-log2(x+6)=3-log2(x+2)∴log2[(x+14)/(x+6)]=log2[8/(x+2)]∴(x+14)/(x+6)=8/(x+2)且(x+14)/(x+6)>

解方程log2(2x+1)=log2(x^-2)

由题意定义域2x+1>0x^2-2>0则x>√2而x^2-2=2x+1则x=3或x=-1则x=3

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)=

解方程(1) log2(4²+4)=x+log2(2^x+1-3)

log2(4^x+4)=log2(2^x)+log2[2^(x+1)-3]令2^x=a4^x=a²2^(x+1)=2alog2(a²+4)=log2(a)+log2(2a-3)lo

解方程:log2(3-x) - log4(x+5) =1

log2(3-x)-log4(x+5)=1log2(3-x)=1+log4(x+5)log4(3-x)²=log44(x+5)(3-x)²=4(x+5)x²-6x+9=4

方程log2[9^(x-2) +7]=2+log2[3^(x-1) +1]的解为

log2[9^(x-2)+7]-log2[3^(x-1)+1]=2即log2[(9x-11)/(3x-2)]=2(9x-11)/(3x-2)=4所以x=-1但又因9^(x-2)+7大于0所以x大于11

方程log2(2x+1)log2(2x+1+2)=2的解为______.

由题意可知:令t=log(2x+1)2,则t(t+1)=2,所以t=1或-2.由log2(2x+1)=1,可知x=0;由log2(2x+1)=-2,可知无解;所以方程的解为0.故答案为:0.

解方程:log2(4^x+4)=x+log2(2^(x+1)-3)

log2(4^x+4)=log2(2^x)+log2[2^(x+1)-3]令2^x=a4^x=a²2^(x+1)=2alog2(a²+4)=log2(a)+log2(2a-3)lo

解方程:log2(9^(x-1)-5)-log2(3^x +2)-2=0

log2(9^(x-1)-5)-log2(3^x+2)-2=0log2(9^(x-1)-5)=log2(3^x+2)+log2(4)log2(9^(x-1)-5)=log2(3^x*4+8)9^(x-

log2(3^x-1)log(3^x-1/3)=2 解方程

题目是这样的吗?后面是不是lg?如果是,先换底.然后……

方程log2(x-1)=2-log2(x+1)的解为______.

∵log2(x-1)=2-log2(x+1)∴log2(x-1)=log24x+1即x-1=4x+1解得x=±5(负值舍去)故答案为:5