证明：设a^n=xa^m=y由指对数互化得log(a)x=n,log(a)x=m 则log(a)x+log(a)y=m+n∵log(a)xy =log(a)x+log(a)ylog(a)xy=log(a)a^n*a^m∴log(a)a^n*a^m=log(a)x+log(a)y=m+n由指对数互化得a^m×a^n=a^（m+n）,得证...