=lime^[(a^xlna+b^xlnb+c^xlnc)/3]=[e^(lna+lnb+lnc)]^1/3求解这一步是怎么来的………

=lime^[(a^xlna+b^xlnb+c^xlnc)/3]=[e^(lna+lnb+lnc)]^1/3求解这一步是怎么来的………
=lime^[(a^xlna+b^xlnb+c^xlnc)/3]
=[e^(lna+lnb+lnc)]^1/3
求解这一步是怎么来的………

=lime^[(a^xlna+b^xlnb+c^xlnc)/3]=[e^(lna+lnb+lnc)]^1/3求解这一步是怎么来的………
令y=e^(a^xlna+b^xlnb+c^xlnc)/3
那么lny=(a^xlna+b^xlnb+c^xlnc)/3
两边取极限的
lim(lny)=(lna+lnb+lnc)/3
而且原来的极限
=lim(e^lny)=e^(limlny)=e^[(lna+lnb+lnc)/3]=[e^(lna+lnb+lnc)]^1/3