limx→0ax−a−xx
limx→0ax−a−xx=limx→0(ax−1)−(a−x−1)x=limx→0ax−1xlimx→0ax−1x=limx→0ax−1x+limx→0a−x−1(−x)=loga+loga=2loge2
limx→0ax+a−x−2x2
limx→0ax+bx−2x
limx→0ax+bx−cx−dxx