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System Message

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

Guest (Customer)

[00:00:00] sum of difference of cubes

Constance G (Tutor)

[00:00:08] Welcome to Tutor.com !
Let's get startedhi

Guest (Customer)

[00:00:11] hi

Constance G (Tutor)

[00:00:37] do you have a problem that involves the sum or difference of cubes you would like to work with?

Guest (Customer)

[00:00:45] i dont jave a specific problem

Constance G (Tutor)

[00:00:59] would you like to walk through an example.

Guest (Customer)

[00:01:02] yes

Constance G (Tutor)

[00:01:24] It is a matter of a pattern, do you know what the sum or difference should look like?

[00:01:59] If not I can put the general form on the board first.

Guest (Customer)

[00:02:33] yes plz

Constance G (Tutor)

[00:02:37] ok

[00:03:28] do you see the pattern?

Guest (Customer)

[00:03:47] yes

Constance G (Tutor)

[00:04:09] now I will have you try an example, I will help when you need me.

Guest (Customer)

[00:04:13] ok

Constance G (Tutor)

[00:04:29] first break the 8 into a cube

Guest (Customer)

[00:04:56] you mean like 4^2

Constance G (Tutor)

[00:05:07] is 4^2 = 8 ?

[00:05:24] what raised to the third power = 8

Guest (Customer)

[00:05:23] ..it hink

Constance G (Tutor)

[00:05:49] for example 5^3 = 125

Guest (Customer)

[00:06:00] 2^3

Constance G (Tutor)

[00:06:10] good that is the first step

[00:06:22] rewrite the problem with the cube.

[00:06:50] sorry I wrote x^2 it should be x^3

Guest (Customer)

[00:07:01] ohkay

Constance G (Tutor)

[00:07:25] next you use the pattern on the right to factor.

[00:07:36] step one is to get the first parenthesis

[00:08:31] what would your a and b equal?

Guest (Customer)

[00:08:41] x and 2?

Constance G (Tutor)

[00:08:45] good

[00:08:56] go ahead and write the first parenthesis

[00:09:59] note that the other parenthesis has three terms.

[00:10:40] first term is squared, then multiply the two terms, change the sign, then add the square of the second term

[00:11:00] see if you can write it for your x and 2

[00:11:31] good

[00:11:50] keep it up

[00:11:57] oops

[00:12:27] are there any cubes in the parenthesis I underlined?

Guest (Customer)

[00:12:44] no but you saud ass thr square
of the second term

[00:12:52] *add

Constance G (Tutor)

[00:13:23] right but first you multiply the two terms which you did, but added on a cube, not part of the pattern

Guest (Customer)

[00:13:32] ok

Constance G (Tutor)

[00:14:09] no cube and you will be okay for that term

[00:14:45] great,

[00:14:53] put a parenthesis on it and you are done

[00:15:08] should we try another?

Guest (Customer)

[00:15:17] yes. thats the answer?

Constance G (Tutor)

[00:15:37] yes it is and correct, you could square the 2 and get 4 but that is okay

Guest (Customer)

[00:15:49] ok

Constance G (Tutor)

[00:16:16] okay, this time see how far you can get without me.

[00:16:46] I will still give you comments

[00:17:00] careful

[00:17:15] what number cubed = 27?

[00:17:29] 3 times 9 = 27

Guest (Customer)

[00:17:42] 3?

Constance G (Tutor)

[00:17:48] right

[00:18:15] now you are ready to factor.

[00:19:00] does the 3 get a power?

Guest (Customer)

[00:19:09] nope

Constance G (Tutor)

[00:19:13] good

[00:19:18] keep going

[00:19:59] check the pattern

[00:21:46] does yours match the pattern underlined in blue?

[00:20:31] You got it!

[00:22:05] that is it.

[00:22:08] nice job

Guest (Customer)

[00:22:10] thanks!

Constance G (Tutor)

[00:22:21] That is the key, follow the pattern

Guest (Customer)

[00:22:26] ok

Constance G (Tutor)

[00:22:46] Hope this has helped they really are a matter of seeing the pattern and following the steps.

Guest (Customer)

[00:22:58] ok thank you

Constance G (Tutor)

[00:23:05] Thanks for using Tutor.com.Â Please fill out the survey as you leave so we can learn how we can better help you in the future!Â

[00:23:13] my pleasure , glad i could help

[00:23:20] have a good evening