(x→∞)lim[(x^2-2)/(x-1)-ax+b]=0,求a与b的值

lim xsin(2/x) x→∞ Lim [x^2/(x^2-1)]^x (x→∞) lim(1+x/x)2x (x→∞) lim(x)lim(x→∞) [(x-1)/(x+1)]^2x 为什么 lim(x->∞) {[(-2)/(x+1)]*2x} = -4 lim x→∞ (x+sin 2x)/2 lim(x→∞)(1-2/x)^2x x/2-1lim(1-2/x)x→∞ lim x→∞(2x+1)/(3x-4) lim(x→+∞) (2/π arctan X)^X lim(x→∞)(1-2/x) (x+1)次方 lim x→∞ x-1/x^2 lim x→∞(1-2/x)^x= lim(x→∞)[1+(1/x)]^x/2 求lim(√x^2+1)-x x→-∞ Lim(x→∞)((2x-3k)/2x)-2x= Lim(x→∞)xsin3/x, 求lim(x→0)x cos 1/x lim(x→∞)x^2/ (3x-1)的极限 ( x+3) lim (------------)的x次方 x->∞ ( x-2) lim(x→0)e^x-x-1/x^2