Homework Help: math

Posted by Priya on Sunday, May 22, 2011 at 11:52am.

what is inverse of this funtion
f(x)=(1 / 3)^x?
I think the answer is

f-1(x)= log base 1/3 of x, but i know im wrong... please help!!! THANK YOU

math - MathMate, Sunday, May 22, 2011 at 12:27pm
Three steps to finding the inverse:
1. interchange x and y.
2. solve for y in terms of x.
3. evaluate f^-1(f(x)) to verify that it gives x as the result.

0. y=(1/3)^x
1. x=(1/3)^y
2. log(x)=ylog(1/3)
=> y=log(x)/log(1/3)=-log(x)/log(3)
or
f^-1(x)=-log(x)/log(3)
3.
y(f(x))
=y((1/3)^x)
=-log((1/3)^x)/(log(3)
=-xlog(1/3)/log(3)
=x OK
math - Priya, Sunday, May 22, 2011 at 12:42pm
THANKS ALOT... I GET IT NOW!!!!!!
math - Priya, Sunday, May 22, 2011 at 12:55pm
THANKS ALOT... I GET IT NOW!!!!!!
math :) - MathMate, Sunday, May 22, 2011 at 3:32pm
You're welcome!

Answer this Question

Related Questions

Calculus - Find the inverse of each relation: y = (0.5)^(x+2) and y = 3log base ...
Inverse of log function - Find the inverse of f(x) = log(2+x) - 4 the base is &...
log graph - How do you graph y= -log (base 5)(-x)? The written question is: ...
graphing - How do you graph y= -log (base 5)(-x)? The written question is: ...
math - Could you show me step by step how to find the inverse of this problem: ...
log equation graph - How do you graph y= -log (base 5)(-x)? The written ...
math - i have 2 math questions i dont understand so if you could help me i would...
Math - these are some problems i do not get any help is appreciated. These are ...
Precalc - 1. 1/3log base 8 of (x+1)=2log base 8 of 3-(2/3)log base 8 of (x+1) 2...
Review of Logs - I can't seem to get the answer to this; the answer key says...

For Further Reading

First Name:
School Subject:
Answer: