二、求极限方法举例 例1求Iim_,xC-1 2x2-3x+5 A: lim(x2-3x+5)=lim x2-lim 3x +lim 5 x→>2 →2 x→>2 (lim x)"-3 lim x+ lim 5 2 x→)2 x→>2 =2-3.2+5=3≠0 lim x-lim 1 ∴原式=n2 x→2 2°-1_7 im(x2-3x+5)33 x→>2二、求极限方法举例 3 5 1 lim 2 3 2 − + − → x x x x 例1 求 解: lim( 3 5) 2 2 − + → x x x lim lim 3 lim 5 2 2 2 →2 → → = − + x x x x x (lim ) 3lim lim 5 2 2 2 →2 → → = − + x x x x x 2 3 2 5 2 = −  + =3 0 lim( 3 5) lim lim1 2 2 2 3 2 − + − → → → x x x x x x 3 2 1 3 − = 3 7 ∴原式= =