lim(x-0)(x^2+2x)cos5x/(x+tan3x)

lim(1-x)^(2/x) x->0 lim(x-0)(x^2+2x)cos5x/(x+tan3x) 求极限lim(x->0)(x+e^x)^2/x lim(x->0)((2-x)/(3-x))^1/x lim x-0(x+e^x)^(2/x)要过程 lim(x→0)e^x-x-1/x^2 lim(x→0)[e^x-e^(2x)]/x lim(x-0)(sin3x*sin5x)/(x^2) lim(x(sin)^2) 1.lim x->∞ （2x/x^2+1)*cosx 2..lim x->∞{ [(x^2-x)arctanx]/x^3-x-5}3..lim x->0 （e^x-e^-x-2x)/(x-sinx) 4..lim x->0 (sinx-x)/(x^3) 5..lim x->0 (x^2*tanx)/(x-tanx) 6..lim x->0 (1+3/x)^2x 7..lim x->0 (1+2x)^(3/sinx) 8.lim x->∞ (x/1+x)^(x-3) 9..li lim(x-->0-)arctan1/x 为什么趋于-2/ lim(x-->0+)arctan1/x 为什么趋于2/ (1) lim(x->正无穷) x-lnx (2) lim(x->0+) cosx^1/x^2 X趋于0 Lim(xlnx)=Lim(lnx/(1/x))=Lim(1/x/(-1/x^2))=Lim(-x)=0Lim(lnx/(1/x))=Lim(1/x/(-1/x^2))其中这步使怎么转化的? lim(x→0)(cosx-cos^2x)/x^2 lim(x→0) (3x^2-5x+2), lim(x->0)(x^2+2x)cos5x/sin2x lim(x趋向0) x^2 / (sin^2) * x/3 (x->0) lim(2x^2-sinx)/x=?