lim (ax²+bx+1)/(x-1) as x->1 = 3
设ax²+bx+1=(x-1)(Ax+B)=Ax²+(B-A)x-B
A=a,B=-1,b=-(1+a)
∴lim (x-1)(ax-1)/(x-1) = 3
lim (ax-1) = 3
a-1=3
a=4,b=-(1+4)=-5
lim [b^x+a^(x-1)]/[a^x+b^(x-1)] as x->1
= lim [(-5)^x+4^(x-1)]/[4^x+(-5)^(x-1)]
= (-5+1)/(4+1)
= -4/5
与你的答案不同,能否说声到底x趋向啥数值?这里莪暂时当是x趋向1.