Don't know where to start

[elcatracho]

Hey I have this question that states... If f^-1(x) is the inverse of
f(x) 2e^-x, then f^-1(x)=? I don't know how to start this question other than to swtich the x's with y's but what is the answer from there? Can anyone help me please?

 

[stapel]

I'm going to guess that an "equals" sign was omitted, and that the question statement says that "f(x) = 2e^-x".

To find the inverse, the general process is:

. . . . .1) Rename "f(x)" as "y".
. . . . .2) Solve for "x=".
. . . . .3) Switch "x" and "y".
. . . . .4) Rename the new "y" as "f^-1(x)".

In this case, you would have:

. . . . .y = 2e^-x

To solve for "x=", start by taking the log of each side.

Eliz.