2log5(15)-log5(18)+log5(2) 急

问题描述:

2log5(15)-log5(18)+log5(2) 急

2log5(15) - log5(18) + log5(2)
=log5(15^2 - log5(18) + log5(2)
=log5(225 ÷ 18 × 2)
= log5( 12.5 × 2)
= log5(25)
= log5(5^2)
= 2