# Tutor.com Functions Session

##### Dec. 11, 2012

Session Transcript - Math - Calculus, 11/20/2012 4:44PM - Tutor.comSession Date: 11/20/2012 4:44PM
Length: 14.8 minute(s)
Subject: Math - Calculus

System Message
[00:00:00] *** Please note: All sessions are recorded for quality control. ***

Tyler (Customer)
[00:00:00] g

Kristen C (Tutor)
[00:00:04] Hello!
[00:00:10] Welcome to Tutor.com . How can I help you?

Tyler (Customer)
[00:00:54] how do i find the inverse function?

Kristen C (Tutor)
[00:01:05] OK!
[00:01:15] Do you remember the name of the technique your teacher taught you?

Tyler (Customer)
[00:01:20] no
[00:01:28] i have a ti 89
[00:01:35] if it will do it?

Kristen C (Tutor)
[00:01:45] It's actually easier on paper.

Tyler (Customer)
[00:01:53] alrighty

Kristen C (Tutor)
[00:02:03] The steps are pretty simple:
[00:02:34] First, you rewrite the equation, but you SWITCH the variables around.
[00:02:55] Sometimes I like to first write the f(x) as a "y" instead to make it easier.
[00:03:09] Would you like me to show you what I mean?

Tyler (Customer)
[00:03:13] sure

Kristen C (Tutor)
[00:03:32] OK. So, since f(x) just means "y"....
[00:04:03] I can just rewrite the equation with a y instead of f(x). Make sense so far?

Tyler (Customer)
[00:04:11] yes

Kristen C (Tutor)
[00:04:48] OK, now, like I mentioned before, we want to actually switch the x and y around.
[00:05:12] So, you'd write the equation, but instead of "y", you write "x", and instead of "x" you write "y."
[00:05:24] Does that step sound familiar at all?

Tyler (Customer)
[00:05:39] yes

Kristen C (Tutor)
[00:05:49] OK, great. Would you like to try that step?
[00:06:22] OK, great!
[00:06:26] Any idea what you'd do next?

Tyler (Customer)
[00:06:31] no

Kristen C (Tutor)
[00:06:46] OK. Then, we just have to solve for y.
[00:06:54] So that it reads "y = ....."
[00:07:16] What would we do first to solve for y?
[00:07:51] Great job!
[00:08:07] Exactly.
[00:08:17] And that's all you do!

Tyler (Customer)
[00:08:16] and
[00:08:25] wats the purpose
[00:08:28] ?

Kristen C (Tutor)
[00:09:09] Well, the are certainly times where finding the inverse function is necessary. But the interesting thing is that not every function has an inverse.

Tyler (Customer)
[00:09:12] wats the proper way to write this
[00:09:17] expression
[00:09:18] ?

Kristen C (Tutor)
[00:09:46] Just how you have it is perfect.
[00:10:00] Well - one adjustment....
[00:10:25] But otherwise, the rest is just great.
[00:10:34] Some might right the right side as: (x-5)/8
[00:10:36] Either way.
[00:11:07] ANy questions about how to do that?

Tyler (Customer)
[00:11:08] same same

Kristen C (Tutor)
[00:11:20] Exactly, same thing.
[00:11:32] Or are there any other problems that you'd like to go over?
[00:11:58] Basically, the two main steps are: switch the x and y, then solve for y.

Tyler (Customer)
[00:12:12] ok thankyou

Kristen C (Tutor)
[00:12:19] You're welcome!
[00:12:24] Anything else I can help you with today?

Tyler (Customer)
[00:12:51] naw so wats the -1 thing indicate
[00:12:59] is that the inverse symbol?

Kristen C (Tutor)
[00:13:01] That's just the symbol for "inverse"
[00:13:03] Right.

Tyler (Customer)
[00:13:06] ah got ya
[00:13:14] i wish i was smart at math
[00:13:18] im very forgetful

Kristen C (Tutor)
[00:13:32] That can certainly make it hard!

Tyler (Customer)
[00:13:49] well i just got daignosed with adhd
[00:13:55] but i think its getting better ha

Kristen C (Tutor)
[00:13:59] Being successful with math is a lot about doing the same problems over and over....just to repeat the steps.

Tyler (Customer)
[00:13:59] well bye bye

Kristen C (Tutor)
[00:14:07] That's great, I"m glad it's getting better!

Tyler (Customer)
[00:14:10] yea im pretty

Kristen C (Tutor)
[00:14:11] Stick with it!

Tyler (Customer)
[00:14:16] good at regular algerbra

Kristen C (Tutor)
[00:14:21] That's great.

Tyler (Customer)
[00:14:26] have a good one

Kristen C (Tutor)
[00:14:30] Just keep working hard.
[00:14:31] You too!
[00:14:40] Thanks for using Tutor.com ! Enjoy your day!