2lg5/lg2*2lg2/lg3*2lg3/lg5=多少,
问题描述:
2lg5/lg2*2lg2/lg3*2lg3/lg5=多少,
答
2lg5/lg2*2lg2/lg3*2lg3/lg5
=4lg5/lg3*2lg3/lg5
=82lg5/lg2*2lg2/lg3*2lg3/lg5=4lg5/lg3*2lg3/lg5这一步怎么来的?lg5/lg2*lg2/lg3=lg5/lg3(把lg2约分掉)2lg5/lg2*2lg2/lg3=42lg5/lg3