求f(x)=log3 (x)/(x-1)的反函数,(x>1)

来源:学生作业帮助网 编辑:六六作业网 时间:2024/12/24 01:12:22
求f(x)=log3(x)/(x-1)的反函数,(x>1)求f(x)=log3(x)/(x-1)的反函数,(x>1)求f(x)=log3(x)/(x-1)的反函数,(x>1)解x/(x-1)=(x-1

求f(x)=log3 (x)/(x-1)的反函数,(x>1)
求f(x)=log3 (x)/(x-1)的反函数,(x>1)

求f(x)=log3 (x)/(x-1)的反函数,(x>1)

解x/(x-1)=(x-1+1)/(x-1)=1+1/(x-1)
由x>1,故x/(x-1)>1
即f(x)=log3 (x)/(x-1)>0
即y>0
由y=f(x)=log3 (x)/(x-1)
得3^y=x/(x-1)
即3^yx-3^y=x
即3^y=(3^y+1)x
即x=3^y/(3^y+1)

f(x)=log3 (x)/(x-1)的反函数
为y=3^x/(3^x+1)(x>1)