lim[(x-4)/(x-3)]^x x趋向无穷大 求极限

lim x-1/x平方+3x-4 x-1 lim (x->0) sin(3x)+4x/xsec(x) 求导 lim（x->0) x-sinx/x^3+x^4 lim(x+1)^x+1(x+3)^x+3/x^2x+4 x趋于无穷 lim (x->0) 3x/(sinx-x) lim(x+e^3x)^1/x (lim) x/(x-y) lim (x^3-x^2+4x)/(x^2+x) x→ 0 lim(x->2) {(3x+16)^1/2-4}/x lim x→∞(2x+1)/(3x-4) 关于极限1.lim((x^-1) + (x^-4))/((x^-2) - (x^-3)) x-> 正无穷2.lim ((e^x) - (e^-x))/((e^x) + (e^-x)) x-> 负无穷 lim（x-3/x+1）^x lim趋向无穷大 1、lim(x->无穷大) e^x arctanx2、lim(x->0)sinx√1+sin(1/x)3、lim(x->无穷大)【（√x^2+x+1）-【(√x^2-x+1)】4、lim(x->无穷大)((x+{x+(x)^0.5]^0.5}^0.5)/(2x+1)^0.55、lim(x->0)(sin3x+x^2sin1/x)/((1+cosx)x)6、lim(n->无穷大)(2^n)(si lim x→1 (x^2-4x+3)/(x^4-4x^2+3) lim ( x^3+4x+1)/(x^4+5x+4) x→无限 lim(x→∞)(4x^3+2x-1)/(2x^3-3x+1) lim(x→∞)(7x^3+4x)/(2x^3-x^2+3)=? 求极限lim(x→2)(x^2-3x+2)/(x^2+4x-12)