Lim(x趋向无穷)[(x^2-6x+8)/(x^2-5x+4)]?

Lim(x趋向无穷)[(x^2-6x+8)/(x^2-5x+4)]? lim(x趋向无穷)[1-(2/x)]^3x lim(x趋向无穷)-(x+1)+√(x^2+1) lim(x趋向无穷）(cos1/根号x)^2x lim （x 趋向于无穷)e^-x^2*cosx 【求极限】(x趋向正无穷)lim((x^2)/arctanx). lim(xsinx)/x^2-4,x趋向于无穷 lim xsinx/(x^2-4) x趋向正无穷要用迫敛性证, lim(x+5/x-5)^x(x趋向无穷) lim x趋向无穷 {（2x^3+x)sin (2/x) }/ x^2+1 求lim (sin^2x+x)/(cos^2x-x) x趋向于无穷 lim(arctan1/x)/(1/x),x趋向于无穷,为什么? x趋向无穷,则lim(x*a^x)= lim(x趋向于无穷)(1+3/x)^(x-3) lim （n趋向无穷）（x/1+x)x次方 lim趋向正无穷(x+1/x)^3x lim sin(x-1)/x-1 x趋向无穷 lim趋向正无穷(x+1/x)^3x