(x+1)/(x-2)
=(x-2+3)/(x-2)
=1+3//(x-2)
则令1/a=3/(x-2)
所以2x-1=6a+3
所以原式=lim(x→-∞)(1+1/a)^(6a+3)
=lim(x→-∞)[(1+1/a)^a]^6*(1+1/a)^3
=e^6 (x+1)/(x-2)
=(x-2+3)/(x-2)
=1+3//(x-2)
则令1/a=3/(x-2)
所以2x-1=6a+3
所以原式=lim(x→-∞)(1+1/a)^(6a+3)
=lim(x→-∞)[(1+1/a)^a]^6*(1+1/a)^3
=e^6