对数函数:一般地,函数y=logax(a>0,且a≠1)叫做对数函数,也就是说以幂(真数)为自变量,指数为因变量,底数为常量的函数,叫对数函数。
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指数函数:y=a^x,(a>0且a≠1)
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幂函数:一般地.形如y=xα(α为有理数)的函数,即以底数为自变量,幂为因变量,指数为常数的函数称为幂函数。例如函数y=x0、y=x1、y=x2、y=x-1(注:y=x-1=1/x y=x0时x≠0)等都是幂函数。
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扩展资料:
常用对数:常用对数:lg(b)=log 10b(10为底数)
自然对数:对数函数自然对数:ln(b)=log eb(e为底数) e为 无限不循环小数,通常情况下只取e=2.71828