lg(x^2-xy)已经化的够简洁了,不能再化.它不同于lg(x^2)-lg(xy),
lg(x^2)-lg(xy)=lg(x^2/xy)=lg(x/y)
指数函数基本性质:
1、a^(log(a)(b))=b
2、log(a)(a^b)=b
3、log(a)(MN)=log(a)(M)+log(a)(N)
4、log(a)(M÷N)=log(a)(M)-log(a)(N)
5、log(a)(M^n)=nlog(a)(M)
6、log(a^n)M=1/nlog(a)(M)
其他性质:
1.换底公式
log(a)(N)=log(b)(N)÷log(b)(a)
2.log(a)(b)=1/log(b)(a)