1.
y=log2(x^2-2x+2)=log2[(x-1)^2+1]>=log2(1)=0
定义域为R,值域为[0,∞)
2.
y=log2(x^2-2x+3))=log2[(x-1)^2+2]>=log2(2)=1
定义域为R,值域为[1,∞)
3.
lg(x^2+mx+1)值域为R
对数有意义,x^2+mx+1
1.
y=log2(x^2-2x+2)=log2[(x-1)^2+1]>=log2(1)=0
定义域为R,值域为[0,∞)
2.
y=log2(x^2-2x+3))=log2[(x-1)^2+2]>=log2(2)=1
定义域为R,值域为[1,∞)
3.
lg(x^2+mx+1)值域为R
对数有意义,x^2+mx+1