已知lga+lgb=2lg(a-2b)(a>0b>0且a>2b)求lga-lgb除以lg2
问题描述:
已知lga+lgb=2lg(a-2b)(a>0b>0且a>2b)求lga-lgb除以lg2
答
因为a>b>0,将上式分解,上式可化为(a_4b)(a_b)=0,则a=4b,将所求式化简为 (lga/b)/lg2=(lg4)/lg2 =2
已知lga+lgb=2lg(a-2b)(a>0b>0且a>2b)求lga-lgb除以lg2
因为a>b>0,将上式分解,上式可化为(a_4b)(a_b)=0,则a=4b,将所求式化简为 (lga/b)/lg2=(lg4)/lg2 =2