a,t都是底数,
a>0 and a≠1
t>0 and t≠1
t=a^x,x≠0,
(1)
loga(t/a^3)=logt(y/a^3)
loga(a^x /a^3)=log a^x (y/a^3)
x-3= log a^x (y)-3/x
loga(y)=x^2-3x+3
y=a^(x^2-3x+3) a>0 and a≠1,x≠0.
(2)
f(x)= a^(x^2-3x+3) a>0 and a≠1,x≠0.
x^2-3x+3=(x-3/2)^2+3/4
当3/2≤2a,
a≥3/4,
3/4≤a1,
当3/2≥3a,
0