解：
原式 = [ ( 1 + x + x^2 + o(x^2) ) -1 - x ] / { [ 1- (1/2) x - (1/4) * x^2 + o(x^2) ] - [ 1 - (1/2!) * x + (1/4!) * x^2 + o(x^2)] }
= [ x^2 + o(x^2) ] / { [ - (7/24) * x^2 + o(x^2)] }
= [ 1 + o(1) ] / [ - (7/24) + o(1)]
故
lim { 原式 } = 1/ ( - 7/24) = - 24/7
