t=-x ∴im(1+-)=lim(1-)=lim(1+ t→》+0 lim(1+ 十 t-1 (1+-) A t=-, lim(1+x)=lim(1+ x→>0 lim(1+x=e x→0令 t = −x, t t x x x t − →− →+ + = − ) 1 ) lim(1 1 lim (1 t t t ) 1 1 lim (1 − = + →+ ) 1 1 ) (1 1 1 lim(1 1 − + − = + − →+ t t t t = e. e x x x + = → ) 1 lim(1 , 1 x 令 t = t t x x t x ) 1 lim(1 ) lim(1 1 0 + = + → → = e. x e x x + = → 1 0 lim(1 )