设函数f(x)=x^2-x+b,且满足f(log2(a)=b,log2[f(a)]=2(a>0,a不等于1) 求f(log2(x)的最小值及对应的x值若f(log2 x)>f(1),且log2f(x)<f(1),求x的取值范围

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设函数f(x)=x^2-x+b,且满足f(log2(a)=b,log2[f(a)]=2(a>0,a不等于1) 求f(log2(x)的最小值及对应的x值若f(log2 x)>f(1),且log2f(x)<f(1),求x的取值范围

设函数f(x)=x^2-x+b,且满足f(log2(a)=b,log2[f(a)]=2(a>0,a不等于1) 求f(log2(x)的最小值及对应的x值若f(log2 x)>f(1),且log2f(x)<f(1),求x的取值范围
设函数f(x)=x^2-x+b,且满足f(log2(a)=b,log2[f(a)]=2(a>0,a不等于1) 求f(log2(x)的最小值及对应的x值
若f(log2 x)>f(1),且log2f(x)<f(1),求x的取值范围

设函数f(x)=x^2-x+b,且满足f(log2(a)=b,log2[f(a)]=2(a>0,a不等于1) 求f(log2(x)的最小值及对应的x值若f(log2 x)>f(1),且log2f(x)<f(1),求x的取值范围
1.f(x)=x^2-x+b,且f[log2(a)]=b
所以log2 a)^2-log2 a +b=b
log2a(log2a-1)=0,a≠1
所以a=2
log2 [f(a)]=2,即log2 f(2)=2
log2 (2+b)=2,所以b=2
f(log2 x)=(log2 x)^2-log2 x+2
=(log2 x-0.5)^2+7/4
当log2 x=0.5,x=√2时,f(log2 x)取最小值7/4
2.f(log2 x)>f(1)
即(log2 x)^2-log2 x+2>2
log2 x>2 或log2 x2或0

1、f(x)=x²-x+b,且f[log2(a)]=b
所以[log2(a)]²-log2(a)+b=b
[log2(a)]([log2(a)]-1)=0,a≠1
∴a=2
log2 [f(a)]=2,即[log2f(2)]=2
[log2(2+b)]=2
∴b=2
f(log2[x])=(log2[x])...

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1、f(x)=x²-x+b,且f[log2(a)]=b
所以[log2(a)]²-log2(a)+b=b
[log2(a)]([log2(a)]-1)=0,a≠1
∴a=2
log2 [f(a)]=2,即[log2f(2)]=2
[log2(2+b)]=2
∴b=2
f(log2[x])=(log2[x])²-log2(x)+2=(log2[x]-0.5)²+7/4
当log2[x]=0.5,x=√2时,f(log2[x])取最小值7/4
2、f(log2[x])>f(1)
即(log2[x])²-log2(x)+2>2
∴log2(x)>2 或log2(x)<0
∴x>2或0log2[f(x)]即log2(x²-x+2)<2
0解得
-1综上所述{x|0

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