ln2+ln3解析：(x→0)lim(2^x+3^x-1)/(kx)=1故，(x→0)lim(2^x+3^x-1)/(kx)=(x→0)lim(2^x+3^x-1)'/(kx)'=(x→0)lim(2^xln2+3^xln3)/k=(ln2+ln3)/k=1所以，k=ln2+ln3
