Posted by Christian on .
Determine whether the following statement makes sense or does not make sense, and explain your reasoning (modified from true/false format of text): If
f(x) = 3x, then f^1 (x) = 1/3x
A) This makes sense because the inverse would divide by 3 to "undo" the multiplication by 3 in f(x).
B) This does not make sense because although we would divide by 3 to "undo" the multiplication by 3 in f(x), the x would appear in the numerator not the denominator.

Math (Ms. Sue Please Help) 
bobpursley,
You have to be careful with the term inverse funtion.That is not the same as reciprocal.
if f(x)=3x=y
then the inverse can be found this way:
y=3x
x=3y
y=x/3 or f^1(x)=x/3
check: inverse(function)must equal x
so f^1 (f)= 3(x/3)=x so in fact it is the inverse.
So false. Go with B. When dealing with functions, the term "inverse" seldom means reciprocal. 
math 
Christian,
Please help HM

Math 
Christian,
are u sure about this

Math (Ms. Sue Please Help) 
Ms. Sue,
Christian  Bobpursley is a math/physics/teacher. HM is probably a high school student.

Math (Ms. Sue Please Help) 
bobpursley,
Yes, Christian. But don't trust me. http://www.youtube.com/watch?v=Ec5YYVxyq44 That is the same message.